Uh, maybe she's not physically attracted to you at all, but likes all else. But, w/o sexual attraction, it can't be a romantic relationship. Or, if she could be attracted to you, but itsn't, maybe it's the nice guy syndrome. Yahoo personals had a good article on why nice guys (and girls) finish last. It's a value thing. When you are there, eager, easy, needy, available, no challenge it all equals you aren't "valuable". There's no chase. There has to be a sense of competition against others to get you. Subliminally your easy to win over-ness says to her, you aren't valuable. It's that stupid human instinct and it's a mind game and I think it's dumb. Besides, if she's your best friend and you tell her EVERYTHING, maybe she doesn't like how you've treated the women in your life, or she knows what a push over YOU have been in those relationships. Something is missing in the formula. Attraction? Competition? Your selfishness? Your weakness? Your inability to communicate? Your height? Your bad breath? Your B.O.? Your lack of sensuality? Yes, it could be anything.... Oh, and as for her flirting. RU sure? What is it she does to flirt? That's just mean if she knows she's flirting and teasing. Or, the sex isn't worth losing you as a good buddy and source for attention when she needs it.