For anon who's straight but likes a girl:
I have a friend who's straight, he's only ever been with girls, but there is one boy he likes. We still consider him straight, even though he does like that one boy because he doesn't find all boys attractive or even a few; just the one.
And, if you're terrified of talking to your friends, I'd suggest trying to figure out if they're offended of 'gays' before doing anything else. Hopefully, they’re not too closed-minded to find it just as acceptable.
Then, if all your friends, including the one you think you have feelings for, seem to be OK with it, I’d probably pull aside the one friend and explain what you’re feeling. Don’t be overbearing and insist that she like you back, just tell her you think you have feelings for her, but that you’re not sure. If she’s really your friend, she’ll hopefully try to get through this with you.
Of course, you don’t have to take my advice; this is all opinion.