I've made it no secret that I have anxiety and obsessive-compulsive disorder. A lot of it crops up as intrusive thoughts. And it's not intrusive thoughts like getting a song stuck in your head. It can be VIOLENT it can be SEXUAL it can be GROSS and WEIRD and it's a wholly upsetting brain process to deal with.
Social anxiety also factors into this. The feeling of being perceived and judged is overwhelming even for non-anxious people, but those thoughts get caught in the thought process like the world's fastest turbine which can turn a simple criticism into an apocalyptic nightmare.
The constant looming of thinking everyone thinks less of you just because of who are you. People hating you for your mere existence. And the modern internet certainly doesn't help any of that.
I'm much better about it these days but I feel for anyone who goes through the same thing.