When a man thinks he is not good enough for his partner due to thier amazing beuty, talent, charm etc. Derived from Billy-Bob Thorton's post-divorce comments in which he stated that he didn't think he was good enough for Angelina Jolie and that she deserved someone better than himself.
"My boyfriend always thinks I'm going to leave him and says I should find someone better than him. He so has Billy-Bob complex!"