Tell him " Did you hear it from me" "did i tell you" if he says no then say "then why do you believe what other people say how would you like it if I had done the same thing to you of what you're doing to me"... This always works for me :)
What to say to your boyfriend that thinks you're cheating on him? I'm 16 and he's 17. We've been together for 5 months...