Ok guys I need some more help from you guys.?

Ok so Im in a relationship at the moment with probably the best looking girlfriend I have had yet and I don't think I could break up with her because she really likes me. But I think I am in love with my best friends but her parents are very strict and we can't date till we are seniors. And I decided to wait it out with my current girlfriend to see how things turn out(My best friend also says she loves me and understands my decision) but since I'm not the ugliest guy in school I have enough ex's to be called a player but I ure you I am not. They just all had bitc*ie attitudes. But back to the problem. My ex is best friends with my best friend as well and just asked her to ask me if I would break up with my girlfriend to get with my ex. She knows I can't say no to my best friend. And my best friend is begging me to do it. She can barley stand my ex and just wants it to be over. How do I maneuver myself out of this without losing my best friend and getting rid of my ex for good? Thanks for the answers and please be mature thanks!