From The Book of Questions by Gregory Stock.

Question #54: What is the worst psychological torture you can imagine suffering? Anything causing even minor physical injury should not be considered.

I think the worst thing for me would be to see someone else getting physically tortured. I don't know if that counts since there is a physical element, but it might since nothing would physically be happening to me.

you'd have to really do something horrible to put me through the wringer at this point LOL. i suffer enough from MIs as is, so psychological pain is my middle name.

There's quite a lot I can think of, as someone who spends too much time thinking and inside their own head.
I think a major one would be like, being led to believe your life was a certain way and then suddenly discovering that everything you've known was absolutely wrong and awful. Or, basically, gaslighting to an extreme, where the torture just never really ends and it constantly pulls you in and out of the pain and doubt, while also never really being intense enough to make you breakdown, so you also begin to doubt if you're actually being tortured or not. That would really mess up a person, I think, and I have trouble reading explicit accounts of stuff like that happening to real people.

Psychosis... when ritalin's effect backfires on me. I was supposed to take another med called strattera but since I was on a major project with a tight deadline, my psychiatrist prescribed fast acting ritalin for me to cope with the workload. Ritalin worked almost instantly and I had no problem sitting in class or doing my assignment but the withdrawal hit HARD. 15 minutes ago I was hanging out with my friends all excited and talking about what we'd do the next day but the minute I left them to board the bus, my brain started going crazy. I had these thoughts about my family, friends, everyone betraying and backstabbing me, it just went on and on. I tried pulling my hair and constantly whispering 'stop' to get my brain to shut down but it just wouldn't let go of these irrational thoughts. I was so helpless at that time it's like alien thoughts kept being injected into my brain and I couldn't even control it, also knowing that no one would be able to help even if they wanted to because it's all in my head. At one point I wanted to just bang my head and pass out but I was so preoccupied I couldn't even do that.