My BD has a history of cheating on me and my bestfriend slept with one of my ex boyfriends( when i was dating him) well like 2 months ago they were working cab together and they kept calling me making jokes about them having sex....not funny for me. well it doesnt help that he is ALWAYS flirting with her. when i confront him hes denies it. i have a really really strong feeling they did stuff...i dont know what to do. neither of them will admit it. when i asked my other bestfriend if she knew anything she said no but i have a feeling she does. what do i do??? i need to know.