i had feelings for a few female friends when i was about 14/15. i found that it was a phase, as since then i've never had a crush on a girl again, and in fact the idea really turns my stomach now (i'm now 18). it could just be a phase. i really think you should leave it, as she is your friend and probably won't have the same feelings to reciprocate. if it IS a phase then you'll be glad you did... if it isn't, it is probably better to leave it anyway, as friendships often last much longer than relationships. i think you should wait it out, basically, and see how you feel in a few months.