I’ve been dating my partner for about two years. when we first started dating they said it was okay with them if I ever got crushes on other people, but it was never brought up again. now I’ve met someone new who likes me back. I still want to be with my datemate, but I also want to date this other person. the only problem is, I know I’m not going to be comfortable with it unless they’re dating each other too. how should I initiate that? I’m not going to force it, but I want to at least try.
You can’t just ask that two people date each other because it would make you comfortable. Even “initiating” without forcing it is a pretty big leap considering you and your partner haven’t discussed being in a triad together, you only briefly talked about having crushes on other people, two years ago.
You need to talk to your partner about how they feel about polyamory. When they said it was okay if you had crushes on other people, did they mean it was okay if you acted on them, or just that they don’t mind you indulging in the attraction of a crush? How do they feel about you dating vs. sleeping with other people? If you do see other people, how do they feel about hearing/knowing about it?
The conversation should start in the abstract so you can get everyone’s feelings out in the open - my advice would definitely NOT be to open with “hey so there’s this person I want to date, so I want you to be okay with that, and also I want you to date them too!” - that is a pretty massive thing to drop on someone and requires excessive emotional leaps on their part. This means you may need to put the brakes on whatever is developing with this new person while you and your current partner work out needs and expectations for transitioning your relationship into new territory.