I want to date my 'friends' Boyfriend

there is a girl in my group of friends, we use to be kinda close but only call eachother 'friends' now out of familiarity (we never hang out together or tell each other things anymore). I'm much better friends with her boyfriend. I hang out with him sometimes, we're growing closer and have more shared interests than he and my 'friend' do. I would never dare make a move on him while he is still seeing her, i respect that he's in a relationship - i dont even flirt with him. But i find myself hoping that they will break up, which really isnt unlikely. If they do ever break up i would want to make a move but i fear my entire friend group turning on me and calling me a bitch. I think me and the guy could be a really good couple, i care about him but i dont want to lose my friends either.