Start going after other girls. She'll get jealous, she'll become more attracted to you, then you can let het know youre attracted to her as well but you're not looking for anything serious. Then try go overcome the number one thing that would stop her from wanting to be your fuck buddy...the fear of being a slut.
Make her feel like it's perfectly natural for friends of the opposite sex to fool around. Make sure yu aren't pushy or needy
_________________
The absolute best inner-game fix I've ever found
LimitlessAlpha.com
If you're one of those guys who reads countless pick-up material yet still has some trouble meeting and seducing women, because of AA or fear of rejection or whatever, this'll fix you up.