So I(24M) have a great female friend (21F). Our entire relationship is based on the fact that we clicked really well with each other and rarely do with other people. Somewhere along the way I caught feelings, we “explored” things a bit, it didn't go anywhere despite a mutual confession of interest. We live an hour apart which had a lot to do with it. I'm willing to make the drive, she wants someone who can be there with no notice. Sucks, but is what it is.
Fast forward to now, she's started seeing someone but doesn't want things to change between us. Problem is, it kinda has to. I need to move on, and our “hangouts” would be considered at the very least emotional cheating if not physical by anyone with half a brain. She insists we're just friends, but I'm very confident that she doesn't cuddle or spend time one on one with her other guy friends, and the sexual tension is unreal. From her SO's POV, if I saw the way she acts when we're alone I'd drop her like a hot potato.
So I need to figure out the best way to tell her things have to stop in the least offensive way possible. For my sake from the “I don't want to watch you date someone else” and “I refuse to be the other guy or emotional support while you sleep with another guy” perspective, for her BF's in the sense that he deserves to not be involved in a love triangle, and from hers that she should pick a side. I don't want to just cut contact with no explanation, and I don't want to burn a bridge on something that could work in the future, but I'll be damned if I know how to say “Hey, we can't be close friends anymore” without coming across as an asshole.
Supposed to see her Saturday. Gotta figure out how to put my foot down gently by then. Advice is welcomed.