Search Results: deciding between 2 guys

Cliff notes:
-Met girl, hit off great, she really likes
-We got into a HUGE fight, we didn't talk for 2 weeks
-During that time, she was talking to another dude, and decided to date him
-Me and her resume friendship, i find out she is dating him, and i tell her upfront i still like her and im willing to date her if she happens to be single
-She obviously still likes me, because she said "well maybe if me and him break up we can try again"
-Right now i'm keeping her on the side as a friend as i approach other girls
-Her bf saw a couple flirty texts between me and her, suggesting dating if she's single again, and doesn't feel comfortable with her talking to me
-Ironically a couple days before, i said "if a guy ever tells you dont talk to someone, then run" and she said "yeah yeah im not stupid" yet she's contradicting herself cause she's SIDING with him and doesn't want him to worry so she's going to talk to me less now

What do I do to save my friendship with this girl? its the only way to keep her interested in me.