I think the story is he meets a girl that he falls head over heels for. He knows that he is not really a good boyfriend and doesn't want to hurt her but he goes for it anyway. He ends up cheating on her and her friend tells her about it (careless whispers). Then he sees in her eyes one night that she knows and he has in fact hurt her. After this he notices that he was an idiot and he really loved her and he is nothing without her. He will never "dance" or have that kind of love with another person ever. So he thinks about going after her agian but he fears that she will hate him and say things to hurt him, and then he reflects and feels stupid for cheating and thought they could have been perfect together, and wonders if his mistake was really a fatal flaw.