if you can't be kind, be quiet. If only people remember that in the "HEAT" of the moment. When we were young, we were told just about the same thing. "If you can't say anything nice, don't say anything at all"
Actions speak louder than words. So don't screw someone over again and again and again, then say "I'm sorry you misunderstood what I said/did". Actions speak louder than your fake words. Your just a lousy person. Nope, no misunderstanding there.