My boyfriend and I have been together 11 months, but about 7 months in he cheated on my with one of my best friends (made out with her) and we took a break, after which he decided he didn't really like her. And of course I really cared about him so I forgave him. But then just after Christmas he friend came to me and said he had "made moves on her" several more times, which meant they made out 3 or 4 more times... And after being thoroughly mad at him, I forgave him again. He said he realized how stupid he had been and wished she had never said anything because he'd already changed himself and I was being pointlessly hurt. But he refuses to stop being friends with her, and I've told him several times how uncomfortable it makes me seeing them hanging around together, but it doesn't mean that at New Years they didn't run around my friend's house throwing cake at each other... But he implied that he wouldn't give up his friendship with her even at the risk of ending our own relationship.
I do trust that they don't have feelings for each other anymore, but it still feels like he doesn't respect my wishes and that he seems to value his relationship wiu her higher than his one with me sometimes. Should I break up with him? What should I do?