Wow. I’m sorry that you have to deal with that. I think that’s terrible.
I know exactly how you feel. We all do. We’ve all dealt with that sick or angry feeling that comes with being insulted or misjudged or wronged when you’re unable to make the other person see reason. You want to yell, “I AM GOOD! I AM RIGHT! I AM NOT STUPID!!” but you either don’t have the voice or the capability.
The best defense I’ve developed for this is to truly open your eyes and your mind and know this for yourself — this man is unhappy. Only miserable, mean-hearted people feel the need to insult and belittle others to try to make themselves better or more powerful. I know… I’ve been one of these mean, insulting people before.
YOU knowing that this is true HAS to be enough for you. And when you really believe it, and repeat that to yourself when you’re bullied or insulted, I think you’ll find a big difference in your feelings. Be calm, repeat the mantra, “I am a person. He is not being a good person, because he’s unhappy.” Be strong in yourself. Your opinion is the one that matters.