I wana win my girl back?

Just find someone for yourself. She is attached, don't hound her or she is gonna think your a stalker and she will be turned off even more. Just say "Thanks for the chat. If you would like to talk sometime in the future, here is my phone #..." and leave it at that. Don't talk to her anymore. If she breaks up with her bf, she may call you, then pursue it. If you don't hear from her, then thats life. But whatever you do, keep looking for someone else. Don't get caught up in a girl you havent seen in 10 years.