In love with my former best friend's girlfriend.

I am totally in love with my former best friend's girlfriend. FORMER best friend because he found out me and her made-out several times. The thing is, she lives in the same appartment as me (although she is mostly at his place), meaning she signed the contract together with me for it. She has her stuff here and all. And she works (thanks to me) on the same working place as me and him, so i drive on the same car as her to work (without him). Her bedroom isn't finished yet, but she said she will stay here when it is. And also, she knows i love her, and she told me to wait, cause things are not going that well with him... I don't want to give up on her, but yeah, it is very difficult for me to see them together... what would you do?