I have a guy like this at work. Some days, I'm sorely tempted to pick up my keyboard and smash it over his head. Our desks are face to face, so he feels entitled to my time and attention while he sits there passing judgment on everything and everyone - including themes that are sensitive/triggering for me (that he knows d*mn well about!) At first I felt obliged to answer to him every time, but over time I just started to ignore him.

Funny thing - he started becoming more and more desperate for my attention (largely because everyone else in the office knew him for what he was and didn't give him their attention anymore). At some point, he started shouting and waving his arms. He brought up controversial stuff, trying to provoke me. I was raging so hard inwardly, but outwardly I said without looking up from my work, "I'm busy." That's it. He kept raving. I kept ignoring. And that's how the power shifted in this dynamic.

Note, though, that this guy never got physical or discriminatory. If he had, I would've gone to our manager straight away. There are lines that should never be crossed; if your situation is that severe, I think JoBo's story fits more than mine here.