A few short questions

Is it fine if I use a link to your FAQ as a reference for some people who are asking about polyamory?

Of course! Please always feel free to link my blog and any of my resources. 

My husband and I are trying to start a triad but we don't really know many people in our area, how would you suggest meeting local polyamorous people?

Check out my FAQ on this!

I feel like I may be polyamorous, but I don't think I know what it exactly means and how I could be it?

Here is my FAQ page on this!

My partner is only okay with me dating women, but can't explain why.

I have a poly relationship with my bf. First he said I could date women but not men (I am pan). Because then he would be jealous. Now I like a man and told my bf, we fought. I don't get it? Why would he be jealous of men and not women I asked him and he doesn't know. Do you have any idea?

First off, if your partner doesn't know how to talk about what's going on in their head, it's okay to ask them to do more introspective self-work. "I have this feeling that I'm going to ask you to act on, but I can't explain what it means or where it's coming from" is a non-starter as far as I'm concerned. This is what I mean when I'm always recommending introspection and self-work. Sitting with your thoughts and feelings, examining their contours, finding words for them - this is a requirement for healthy polyamory. If you're going to act as if your feelings are facts and let them dictate the terms of your reality and your relationships, you should have a solid understanding of what they mean and where they're coming from.

Your partner is asking for something called a One Penis Policy, or OPP. This is common in relationships where the 'primary' couple is a man and a woman, and the woman identifies as bi or pan. Men tend to be more jealous of, and feel more threatened by, other men. It often comes from internalized ideas that penis-in-vagina sex is "real" sex, and therefore two women having sex is somehow less "real," and therefore less threatening. It also comes from assumptions about partnerships, where "the man" is the one in control or in possession of "the woman." Therefore, another woman wouldn't be a threat, but another man would. 

Even if your partner isn't overtly sexist or possessive, these assumptions are super common in our culture and worm their way into the way we think about reality. To most people, i's not an opinion or a worldview, it's just "how things are."

You and your partner should do some reading about OPPs (also called One Dick Rules, or ODRs) in polyamory. You can start here and here. Encourage him to find words for his feelings and start thinking about how he can explain them to you and work out how to manage them in the contect of your polyamorous relationship.

Of course, no one is obligated to, and many people are not able to, research and rationalize themselves out of their fears and feelings. Your partner may choose to just hold to this rule, citing his discomfort. He has the right to choose not to try and 'get over' his feelings, and he may try his hardest and still find it impossible. You can only control your choices: whether you want to stay in a relationship with these terms. 

My partner has a dissociative disorder. Does that make our relationship polyamorous?

I thought I was in a mono relationship, but my girlfriend is a system (she says she doesn't have DID but it's pretty close to it). I suppose if I'm dating everyone in her system it's polyamory. What can I do to make this relationship work?

I'm not an expert on multiplicity, but I do trauma work so I know more about it than the average singlet. For readers who may be confused: DID is "dissociative identity disorder" and is part of a category of dissociative disorders. They are caused by severe trauma early in life that prevents a person's identity from cohering. This creates multiple "alters," or different personalities, within one person, which developed in order to cope with the trauma. Other symptoms include memory issues, time loss, trauma flashbacks, and feeling 'detached' or 'unreal.' Someone with DID or OSDD may refer to themselves as a "system" or "multiple."

To my knowledge, dating someone who is a system does not necessarily mean you're dating all of their alters. Some of them may be too young, not interested in dating, or not interested in dating you.

The best thing to do is to talk to your girlfriend about this. What does she need to make this work? What is her best-case scenario? Are there alters she's especially concerned about, or who she wants you to develop specific relationships with? If so, how does she want you to do this? What are her triggers? What does she want you to do if she switches during an intimate moment? How can you support her through the experiences and symptoms of having a dissociative disorder?

Multiplicity is pretty serious and arises from major trauma, so if your girlfriend is not already working with a therapist well versed in dissociative disorders and trauma, please encourage her to see one or offer to help her find one. If she is already working with someone, ask her whether she'd like you to connect with her therapist to help support you and better understand what she needs from you as a partner.

Check out more resources here:

I'm dating two people, but I also want them to date each other

My husband and I are poly. We've been together since HS and we talked about it a lot before deciding to try and meet people. Well, I met this wonderful girl and I have been dating her for a while. My husband likes her as a friend, and she likes him as a friends as well. However, I'd really like our relationship to include all of us, like we're all in a relationship with each other. Do you have any advice or tips on how to bring it up with the both of them without it coming off weird?

You can't 'want' two people into a relationship. It's fine for you to have a best-case scenario, a daydream, a fantasy, a wish - but two people will either have feelings for each other, or they won't. Just because it's ideal for you doesn't mean it can happen, will happen, or is the best for everyone else.

It's fine to bring it up as a hypothetical, saying something like "Hey Jeremeth, you seem to get along well with Clotilda - would you ever be interested in dating her too?" And then again with Clotilda. Bring it up when you two are alone, so no one feels pressured or awkward.

If they don't seem interested, it's best to drop it. Your desires don't really factor in here - they're two individual people who can want what they want. Don't make it sound like a suggestion or a request. It's not their obligation to try and conjure feelings for another person just because that would make you happiest.

Think through why you want this and whether you can meet those needs and desires another way. Recognize and honor the intimacy they already have as friends, and ask yourself what's missing from that that you're wanting. If it's physical intimacy, consider finding someone interested in a threesome. If it's deeper, more investment in the relationship, continue including her, doing things together the three of you - but recognize that you may not be able to get everything you want from this person and this relationship, if it turns out that they're both not interested in this arrangement.

I'm in a messy situation with two people I've been dating

[Zinnia's note: the original letter writer used an anonymizing system that really confused me, so I've swapped to my own pseudonyms.] I have a 2.5 yrs LDR (Zeus) & a shorter relationship (Hera). Zeus & me decided to try being poly. When I got into a relationship with Hera, Zeus made me break it off. Hera & I still saw each other socially with Zeus's knowledge. Hera broke things off twice because they couldn't handle me being in another relationship. After discussion & research they said they were okay with it. Hera & I put the dating label on it again with Zeus's knowledge. Zeus then gave me a choice: Zeus or Hera. Zeus is okay with an open relationship and a polyamorous relationship later. While Hera says they are okay with all aspects of being poly. Advice?

The person who taught me how to be polyamorous had a motto: "If someone is trying to make you choose, choose the one who isn't." 

It does not sound like Zeus wants to be in a polyamorous relationship. When you started seeing Hera, they "made you" break it off. Then, when you and Hera decided to start dating again, again Zeus made it clear that they didn't want to be in a relationship with you while you're also dating Hera.

Perhaps Zeus is okay with an "open relationship," but it sounds like you two have different levels of comfort and sets of boundaries about what that means. My advice is to identify exactly what Zeus wants in a relationship. Then, identify whether that's something you can provide. If it's not, end the relationship.

Then you need to decide if you want to date Hera. Because the choice isn't a binary between Zeus or Hera; you can decide to date neither! If Hera has needs you can't meet or can't meet your needs - if there's too much baggage hanging around from this mess, if you saw red flags in their choice to continue disrupting your friendship over the fact that you wouldn't date them - don't date them either. If you do, make sure you go in with a clear understanding of the terms of the relationship and ensure that you're both operating with the same definition of "polyamorous relationship."

My partner said she was okay with polyamory when we got together, but is now upset about it

So I’m currently in a long distance relationship with someone who said she was okay with me being polyam from the first date (even before the first date I told her). Now I’m on tour with my band for 6 months and I promised to be monogamous until I got home and we reconnected. I’m 2 months into the tour and she is already freaking out about me wanting to date other people when I get home. I still have a little over 4 months on the road and I'm not really sure how to handle this. 

It sounds like she's not actually okay with you being polyam. If she doesn't want you to see other people while you're on tour, and she is already nervous about you seeing other people when you're not on tour, the issue is that she's threatened by you seeing other people.

Or, it could be that she is feeling insecure because you're gone and she feels like you two didn't talk it out enough before you left, and her wanting to continue the conversation feels to you like "freaking out." 

Either way, I think you're getting distracted by red herrings in your situation. The band tour doesn't really matter; the promise to be monogamous during the tour doesn't matter; her insistence since day one that she's okay with polyamory doesn't matter. What matters is that she is upset and threatened by the idea of you dating other people. That's what needs to be addressed.

You need to identify and clarify your expectations and needs and boundaries with her. "Part of dating me is polyamory. I won't be in a relationship where I can't date other people. If that's not something you're comfortable with, this won't work out." If she insists that she really is okay with you dating other people as long as specific concerns are addressed, ask her to clarify for you what those are and work on a plan to address them.

If she can't - if it seems like she's just trying to argue herself into being able to date you, or that she's assuming that her future self will be okay with something her present self clearly isn't - it's probably best to end things. Don't speak for her, by saying "you say you're okay with this, but you're really not, and I know what's best for you better than you, so I'm going to end a relationship that you want to continue, for your own good." That's never a good way to end things. Instead, frame it as you not being happy in this arrangement, getting the sense that polyamory isn't working between you two, that you aren't able or willing to provide all the emotional baby steps it will take. 

I don't know how to try and date people in my social circles if my non-monogamy is a semi-open secret

I've been dating the same person for 2 years and we've been poly the entire time. Our community and peers think we're slutty because we flirt with others. We're not necessarily out about not being mono but how do you even bring that up to people who aren't open minded anyways? I've been trying to date this other person recently but I can't tell how to bring up polyamory. They know I'm in a committed relationship and that my partner knows I'm openly flirting. I'm at a loss for what to do.

You can't have it both ways - if you're not out to people about being non-monogamous, and you flirt with or pursue other people in front of them, they will assume that something untoward or inappropriate is going on. One could argue that visibly flirting/pursuing others is essentially outing yourself.

If people are not open minded and accepting enough to understand non-monogamy, it's probably not wise to try and flirt with or pursue them. If you're just pursuing other people in front of them, like giving a cute bartender your number while out drinking with them, then they are probably going to be uncomfortable about witnessing what they think is immoral/cheating behavior.

It sounds like you really want to be able to live openly in your community of peers - so it might be best to come out to them. You could do it more formally, sitting down with them and telling them, or you could work with your partner to bring it up more casually, conversationally, just make it known. Secrets and ambiguity make people uncomfortable; if you two talk and joke openly about how you're ok with your partner seeing other people, that usually works better for everyone else.

When it comes to the specific person you're trying to date, you need to be really clear with them! Just knowing that your partner knows you're openly flirting isn't enough. If you want to really make a go of trying to date them, you need to let them know exactly what's going on, how you feel, how your partner feels, what they would (and wouldn't) be getting involved with by dating you. If you don't feel like you can have that conversation, then you should probably let go of pursuing this person. 

I agreed to a polyamorous relationship, but it's not working for me

My girlfriend and I entered into a poly relationship with one of our best friends. I said no at first because I didn't want my relationships with either of them to change, but I eventually said yes because I wanted to keep everyone happy, and at least try even if I still felt uncertain. It's only been a day, but I spent time with our friend today, and although I do love her, I feel it's not romantic love, but I don't want to end it for fear of hurting them both. I don't know what to do.

To "keep everyone happy" is NOT a good reason to do anything. If you don't want to do something, someone else's feelings don't get to override your boundaries or even your preferences.

It sounds like you don't want to date this person. Don't date them, then. Even if it will hurt their feelings or upset your girlfriend. Staying in a relationship you don't want to be in for the sake of someone else is unfair to you and the other people.

Be honest - tell your girlfriend that you agreed to try it more to end the conversation and keep her happy than because you actually wanted to. Say that you've thought about it, tried it out (albeit briefly), and you've realized that you just don't want this arrangement.

Think through your best case scenario so you can have a conversation with a purpose. Do you not want to be part of any polyamorous arrangement, or are you okay with your girlfriend dating this friend and you keeping your relationship platonic? What are your feelings, needs, and desires here? Try to have clarity on what you're asking your girlfriend for, then ask for that.

Once you ask her for what you want (to re-close the relationship; for you to be left out of the new relationship, etc.) then she is free to say "no." If that happens, you are not obligated to stay in a relationship situation that isn't working for you, even if you holding your own boundaries makes other people hurt or upset. It is not your job or obligation to keep everyone happy!

I want to date a couple, but don't know how to approach it.

I have an interest in being a third; there has been more than one instance where I've had an interest in couples I am friends with. Like a specific interest in dating both and not wanting to break them up. But I really have no idea how to approach trying to become a third in a relationship, and it can also be quite stigmatized among monogamous bisexuals which is a bit daunting.

It's not entirely clear from your message whether you want this as a generalized relationship framework, or whether there are specific couples you know who you want to date.

If it's the former - if you're just interested in finding a couple to date - you are in some serious luck. That is something that a LOT of couples want, and you will not have a hard time finding a couple to date! A third person who dates a couple is called a "unicorn," and couples seeking one are called "unicorn hunters." You can read more about this on my FAQ page here!

However, that does mean you will need to do a lot of work to screen people and give yourself permission to say no. It's just like monogamous dating - don't date the first person who likes you. Meet lots of people, know your limits and boundaries, and make sure you end up dating someone who meets your needs and fits your personality. 

If there are specific couples in your life that you'd like to date, it works just like crushing on anyone else. Do what you can to suss out their interest - try bringing up triads/unicorns/non-monogamy and see if they have any general thoughts on it - but in the end, the only way to find out is to ask! It can be frightening to approach people about something that's so misunderstood, but if the couple seems open and safe, the worst they can do is say no!

My partner and I want different types of polyamorous arrangements

My partner and I both identify as being polyamorous. But he would like for all his multiple partners to love and be with one another; I am seeking 2-3 separate relationships. How do we reconcile this? Can we?

It depends on whether, for each of you, these are preferences or needs. If your partner would feel unsafe and uncomfortable and unfulfilled in a more V-type arrangement, or if you would feel suffocated and boxed in and frustrated by a polyfidelitous arrangement, then it's irreconcilable.

But there might be room for compromise. Perhaps your partner would be okay if everyone you're dating and he's dating get along and are friendly, even if they're not all romantically intimate. I know people with polyamorous terms of the relationship that dictate that new partners need to 'gel' with their existing community.

Or, perhaps he'd be happy being in a quad or triad with you, while you also have unconnected relationships as well. Maybe what he's wanting will be provided by a triad or quad and is less about not wanting you to have partners that aren't also his partners and his partners' partners.

So, the next step is to just start talking, and keep talking. Describe your best case and worst case scenarios to each other. Daydream instead of planning. Think through different things that would make you happy. Identify what makes you feel threatened and why. I can't identify the sweet spot that will reconcile this, but you two probably can!

I want to date my best friend and her boyfriend, but I worry that's "messed up"

I think I want a relationship with my best friend and her boyfriend. Am I messed up for wanting that? We all get along so well and I care about both of them so much and I feel fucked up for wanting to be with them that way. For wanting to intrude on their relationship. How do I stop feeling this way?

You are not messed up or fucked up. You are having pretty normal, natural feelings of intimacy for people you are intimate with! Caring about people so deeply that you want a new framework for your relationship is not, in general, a bad thing. Wanting more true, real ways to express and live out your feelings of love and care is not "fucked up."

We live in a world that prioritizes certain types of commitment over others. We feel like we can ask things and expect things of people we are "dating" but not people we are "friends" with. So there is a kind of insecurity that comes from not having a "dating" relationship, and I get it!

The only way that it would be "messed up" is if, in acting on these feelings and desires, you violated boundaries. If you have genuine reason to believe that your friends would be really threatened or put off by you broaching the topic of a shift in the relationship, it might be best to drop the issue. If you don't, it's worth bringing up! Let her know how you feel, what your ideal relationship framework would be, and why.

If she says she's uncomfortable with that, and you keep pushing or trying to convince her to see things your way or trying to underhandedly act as if the relationship has changed and thus manipulate her into it - that would be "fucked up." But all you've done now is have deep feelings for people you're close to, and want to live out those feelings in a more authentic way. There is nothing wrong with that!

I don't know how to tell my ex that I don't want to get back together

My ex recently got back in touch with me and wants to start over. I still kind of have feelings for this person, but I can't see us being happy together because they're monogamous and I'm polyamorous, and they aren't open to the idea of being in an open relationship. I've tried to be mono for them before and while they were happy, it made me miserable, and I don't want to go through that again. I don't know how to tell my ex it won't work between us. What should I do?

"No" is a complete sentence. Consensus is not required here. You don't need to get them to agree, or see things your way. You don't need to convince your ex that getting back together is a bad idea. You can just decline to get back together. You know that dating them made you miserable, and you don't want to do it again. Some lines you can use:

  • "I don't want to get back together with you."
  • "The reason we broke up still exists for me, and I haven't changed my mind."
  • "I know that you want to try dating again, but I don't feel that way."
  • "I'm not going to try and argue or get you to see things my way - you just need to know that my answer is no." 
  • "Please don't ask me again. If you keep trying to push for another relationship with me, I'll have to take a step back from even a friendship."

If they won't take no for an answer, do what you need to maintain your boundaries. Block them through whatever channel they used to get back in touch. Take emotional and physical distance. You have no obligation to "tell them" in exactly the right way. You don't need their permission to not date them. Stop worrying about how to tell them - just tell them, and then walk away.

Is it possible to be neither, or both, polyamorous and monogamous?

How do I identify if I'm comfortable with the idea of both polygamous and monogamous relationships?? I'm either monogamous or polygamous right? I can't be completely happy in both type of relationships?

First off, the correct term is "polyamorous," not "polygamous."

Second, it is entirely possible to be a person who would be happy and fulfilled in a polyamorous or monogamous relationship. Just like there are people who would be equally happy staying at home with kids or working in a career. People who would be equally happy in a relationship with a man or a woman. Very few things in this world are true, all-or-nothing, either-or binaries.

As for an identity term that captures this, there isn't one that is widely used for this, the way we have "pansexual" and "bisexual" or "bigender" and "genderfluid." But some that are out there include:

  • monopoly or polymono
  • polyamorish or monogamish
  • polyflexible or monoflexible
  • biamorous
  • flexiamorous

But, above all, relax! You are who you are, and it's pretty neat that you have available to you a wide range of relationships and partners. Seek partners based off mutual connection, be clear about what you expect of your partners and what expectations of theirs you can and can't meet, and you're golden! 

Is there a term for the specific type of relationship we're looking for?

My partner and I have been together 17 years and we are wanting to bring another male in to our relationship (MMF). What would the correct name be for this relationship? Both males are straight.

Well, for one, I can't quite parse exactly what kind of 'relationship' you're trying to name. If both males are straight, then they probably won't want to be in a sexual or romantic relationship with each other, so the new person probably won't be "brought into" your existing relationship - they'd primarily be with the female partner, right? Dating one person in a relationship is different than "joining" or "being brought into" a two-person relationship. You'd be well served to think a bit more about the specific dynamic you're hoping for, so you can better explain it to yourselves and future partners.

Are you planning for this to be primarily sexual, like someone to have threesomes with? The word for that is really just "threesome" - or "group sex," "multiple partners," that sort of thing. There are specific sexual concepts common in MMF sexuality, like "cuckolding." Are you looking for someone for the female partner to date? That is just called "polyamory," "V-shaped polyamory," or an "open relationship." One person sought after by an existing couple to date that couple as a unit is called a "unicorn." 

There are not, to my knowledge, specific terms for relationship configurations based on the specific number and genders of people involved. I'm not sure we need those, frankly. If you are looking for linguistic validation that what you want is "a real thing," that also doesn't exist, and you don't need it. If you are looking for a very particular term that you think will perfectly describe what you want so that you don't have to do other work of explaining, defining, and communicating, that doesn't exist. You need to continue to do the work of identifying and defining your needs and boundaries.

Can I be polyamorous if I'm straight?

I found out that I’m into polyamorous relationships. I only opened up to one person who is an acquaintance plus I have a crush on and thankfully he took it well but I sort of feel excluded since I don’t considered myself bisexual nor lesbian. Is it okay being interested in one gender while being poly?

Who is making you feel excluded? Those people are wrong and being obnoxious. Being bisexual or lesbian is about who you are attracted to; being polyamorous is about the type of relationship you want to be in. They are completely separate and can be mixed and matched in whatever combination is true for each individual. There are monogamous bisexuals, polyamorous lesbians, monogamous heterosexuals, polyamorous heterosexuals, you name it. Relax - you are you, and if you're polyamorous, then you're polyamorous.

Can you be polyamorous with a preference for monogamous relationships?

Is it okay to be polyamorous with a preference for monogamous relationships?

I'm going to do that annoying thing where I sort of reject the entire premise of the question, and then answer it anyway.

You don't need to ask me whether something about who you are or what you prefer is okay! I'm just some blogger - and there's no almighty arbiter of whether a way of being in relationships or a certain identity is "okay." You do you, in whatever way is healthy and honest for you and your partners.

But since you asked - of course it's okay! Plenty of people fall under the umbrella of "could be happy with A or B, but generally prefers A." Plenty of people could be happy and fulfilled in a polyamorous or a monogamous relationship.

If you want to identify as a polyamorous person, that's fine! You could also identify as polyflexible, monoflexible, monopoly, poly-mono, monogamish, or whatever other term feels right to you. But if you have a preference for monogamous relationships, it might make more sense to actively seek out monogamous relationships instead. The good news is that the majority of people identify as monogamous (whether because of something innate or socialized assumptions), so your preference should be relatively easy to indulge.

Someone told me the point of polyamory is to cultivate jealousy, and I don't want that

Someone I know said they were told by a polyamory person that jealousy is what brings people into polyamorous relationships? Because it's a rush or it provides a constantly "new" and "fresh" feeling to the relationship? I said that wasn't true because polyamory is a relationship (generally) like most others and jealousy in any relationship can make it unhealthy. I just wanted to check because I would like to enter a poly relationship in the future but I don't want to be in that kind of environment.

You are correct in that "purposefully injecting and indulging jealousy" is not typically a healthy relationship dynamic, and it is not at the core of most healthy polyamorous relationships.

Your friend of a friend may have been referring more to the fact that some people get a sexual charge out of what we might call "jealousy." Lots of sexual fetishes, kinks, and fantasies revolve around threat, territorialism, possessing a partner, etc. Perhaps the most recognizable form of this is "cuckolding" or "cuckqueaning," though there are lots of other forms it can take: some people like to include the 'sharing' of a partner as part of a BDSM scenario, some people just include spoken fantasies about other sexual partners as part of their erotic flirting or foreplay.

But this is a sexual thing, not a relationship thing. Jealousy is a powerful energy, and most powerful energies can be eroticized. There is nothing wrong with people seeking other partners as part of their sexual play, as long as everyone is on board and all parties understand and consent to what's going on. But in almost all cases, what works sexually isn't the totality of the relationship, and vice versa.

For most polyamorous people, polyamory is a way of being in a relationship, not a way of having sex. But, there are people out there who do center their polyamory around sex and sexuality. This can create confusion and even stigma, which is frustrating, but language is imprecise and the alternative is gatekeeping and in-group conflict, which I'm generally against unless necessary for people's health and safety. The most important thing is to know what polyamory means to you.

Just because someone out there practices polyamory in a way you would find unhealthy or unpleasant doesn't mean you need to! Someone else's definition of polyamory can not and should not define your own relationships! Your job is to know who you are, and what you mean when you use specific terms and labels. This is important when communicating with people in your life, and less so when it comes to correcting or policing other people. So, yeah, it's aggravating that misinformation is going around through your extended circle, but rest assured that you don't have to agree with or act on other people's beliefs. 

My boyfriend cheated on me, but said it was okay because he's polyamorous

My boyfriend just told me he's been dating someone else behind my back, but it's ok and it's not cheating because he's polyamorous. I don't know the person and from talking to them over the phone they're really annoying. I don't want to lose my boyfriend but also I feel really bad he didn't even tell me he was dating someone else.

What!? Your boyfriend is wrong. Your boyfriend cheated on you, full stop. He doesn't get to tell you what is and isn't okay. If you're not okay with it, it's not okay. 

"I took your stuff without asking, but it's not theft because I'm a communist." No, taking people's things without permission is stealing, even if you don't believe in the concept of private property. They also need to be in on the philosophy. 

What your boyfriend is doing is not practicing "polyamory," but cheating. Polyamory requires open communication and consent of all parties. Just because he has a fancy word for what he's doing doesn't mean you need to go along with it. Stop talking to his other partner on the phone, stop bending over backwards to accommodate his twisted worldview where he can do whatever he wants without consequences. 

Leave this relationship - he cheated on you, acted without your consent, then told you how to feel about it and continued making demands on you. This is not polyamory, it's a person acting cruel and selfish and obnoxious. Dump him. 

Is there a third way out from having to choose between partners who want monogamy & partners who don't?

My wife and I are poly. She has a boyfriend, and I have a girlfriend. Neither the boyfriend, nor the girlfriend are involved in other relationships. They both want more. In fact, they both want to have monogamous relationships, but all of us will be sad if there are breakups. So, aside from either the girlfriend/boyfriend breaking up with us, or the girlfriend/boyfriend being "stuck" in a poly relationship, is there some sort of third option?

No, there is no third option. There will be sadness if breakups have to happen, but there will also be sadness if people are "stuck" in relationships that don't make them happy. There's a choice here that needs to be made, and there's no way out of having to make that choice. Life is full of tough choices, and each path we pursue comes at a cost. It's painful, but it's just part of being a human who has relationships. 

I want to be with a polyamorous guy, but I am mono and I'm not sure it can work

I am a monogamous girl and fell in love with a poly guy. I am a very insecure person and it hurts me just thinking about him being with another girl but on the other side, I understand this is who he is and it doesn’t make his love for me any different. I want nothing more than to be with him, but is it truly possible for a mono and poly person to be together? Any advice would be greatly appreciated!!

The world is a rich tapestry and almost anything is possible. Could *a* mono person and *a* poly person be happy together? Entirely possible. Could *you* be happy with *this* poly guy? Sounds a lot less likely.

It sounds like intellectually, you understand how his polyamory functions; but emotionally, it causes you a lot of pain. That's okay. There are a lot of instances where we 'know' something but still feel differently. It may be that you can't logic and reason yourself out of being monogamous and really needing a monogamous relationship to feel happy and safe. If being with someone "hurts you," then you probably shouldn't stay in this relationship. Incompatibility sucks, but it happens. 

If you want to try and work on this, consider moving out of the framing of "I am a very insecure person" to "I struggle with insecurity." It's not an inherent part of who you are, it's a feeling you have that can be sat with, worked on, interrogated, etc. Ask yourself where those feelings come from, whether they reflect reality, whether they are serving you, and what alternatives might there be. (Even if you don't decide to work on this relationship, that sort of reframing will serve you well in all things.) 

But honestly, it sounds like a core part of who you are and what you need in a relationship conflicts with a core part of who he is and what he needs in a relationship. Don't do yourself the disservice of trying to silence and ignore your very real feelings and needs with over-intellectualizing and excessive sacrifice. If it's hurting you, let go of it.