I was dating a girl who became polyamorous in our relationship. I’m not polyamorous and I don’t think I can change myself to be. I’m very affectionate, touchy, clingy, and I get jealous very easily. I still like her and I will still care for her, We are in the same group of friends by the way I just want to know what a polyamorous person will think or feel about his or her ex. Will her or she still care for them or just ignore him or her?
I can’t really tell you how a person I don’t know will behave after a breakup - every poly person is different, and it’s impossible to predict something like that just based on whether someone identifies as poly or practices polyamory. In my personal experiences, poly folk tend to be pretty good about staying friendly with exes, for a number of reasons, but there are plenty of exceptions.
My advice to you would be to talk about this with her. Let her know that you don’t think you can continue being in a romantic relationship with her because something has changed about the arrangement, but that doesn’t change the fact that you two have lots in common and get along really well. Ask whether she thinks you two can shift to a platonic relationship, building on whatever brought you two together in the first place, but without the pressure of your individual feelings about monogamy and dating. See what she says!
P.S. You didn’t ask about this, but you did write into my advice column, so here’s some semi-unsolicited-advice: you’re well within your rights to only engage in monogamous relationships, but even with an exclusive partner, jealousy and clinginess aren’t healthy. You might want to consider working on whatever fears, beliefs, or habits lead you into those sorts of feelings and behaviors. Liking lots of affection is different than clinginess.