GIRLS i need your HELP!?

ok um let me tell you a lil bout me im sittin bout 5'12 about 140 pounds and most of that is pure muscle. And i play football and basketball and im white. ok now then i have like this bff at my school and shes a girl and whenever we go to a away basketball games we always eat dinner together and that dinner is priceless we have alot of fun and we always flirt... alot and were always near each other sharing drinks and milk shakes, ok me and her like always flirt with each other but thats normal for her because she flirts with every boy that she meets. but me and her are good friends and she told my friends that she liked me but i don't know what to do because me and her are like best friends and i don't want to ruin that ... btw she just rejected one of my fellow basketball players for no reason at all she just said that she didn't want a boyfriend but im sure i could sway her decision if i wanted to. anyways what should i do!