text: Okay, here's the long answer:\n\nFirst, I think people's gender attraction falls somewhere along a scale, with the two extreme ends being people who cannot perform at all with someone of the same gender, or on the other end, the opposite gender. I think most people fall somewhere between the two... but often, how people *act* on their mingled attractions is very different than them just *having* said attractions.\n\nAlso, it *can* take a long time for someone who is bi to admit it to themselves, because it's not socially accepted much at this point. It's even harder for male bis than females, in this.\n\nYour friend may be bi, or she may be lesbian. Point is, does it matter? It's a friend, right? So be friends. And as for your worry that YOU are the 3rd person... well, why not try the novel approach of being straight up and honest with her? :D Look her in the eye and say something like "Hey, I've been getting the feeling that maybe you're attracted to girls as well as guys, and since you won't tell me who the 3rd girl is, I suspect it might be me. So, I'm just gonna put this on the table: you're my friend, and you'll always be my friend---but for me, I can't be anything more than just a friend... I'm just not attracted to other girls. But if you are, that's fine."\n\nIf she's a real friend, she'll respect your honesty---especially if you say all that in a friendly, caring, confident way, rather than acting all nervous.\n\nJust be yourself, be honest and caring, and see what happens. It's the best that any of us can do.\n\n(And yes, I'm bi, tho' most of my attraction is for males; and it took me a lot of years to get past cultural conditioning to admit that there were a few women out there I was physically attracted to enough to wish to do something with them.) :)