He was just a boor. It was a small, very unpleasant incident. Let go of it, or he's won. What if, like my sister, you'd just learnt you had breast cancer. Peace of mind is all about letting go of these petty irritations we all suffer from time to time. They're horrible, but in the scheme of things, they're nothing, are they, really? Yes, you were in the right, and he was in the wrong. So what? Do you know why? He has to live with himself, you don't. Find peace from that. And believe me, what comes around goes around. You don't have to do anything.