I know this feeling very well.I just told mt best friend that I loved her, And she isnt even attracted to me. There is nothing quite like the pain of unrequited love. You wouldnt think that stuff like this should happen. But anyway IT DID!! . My body is quite numb at the moment. Quite why I am telling this to a group of people I have never met before, is beyond me. Just thought i would share.
It's good that you had the guts to tell her how you felt. For better or worse, it moves things forward. If she is your best friend, I guessing she probably needs you to be her friend.
Man, I've done the same thing, but usually I didn't have the nerve to tell the girl how I felt. That just made the feeling strain on way too long. But it seems like I spent much of my teenage life and most of my twenties in situations like that.
Now I'm 32 and it's just not like that anymore. For the past few years the whole 'girls' thing just sort of crystalized. I guess I became more confident, or something... I don't know. Maybe it's a maturity thing. All I'm saying is that if your path is anything like mine- shits going to get easier in this department.
Becoming an established successful musician is still going to elude you though.