shut the fuck up. I fucking hate you. you disgust me. I wish you were dead. you deserve to be miserable and i'm glad that you are. fuck you, you piece of shit, useless, total waste. fuck off and die.
I would never talk to another person the way I talk to myself. No one deserves that.
So! A thing that helped me was to depersonalize my self-hate so it's like I'm viciously ripping into a different person. That makes me feel gross, like a bully or something, and I now do it much less. Gotta have empathy for the stranger that is yourself.
You'd never say "I'm going to fucking kill you. You deserve to die. You are the lowest human scum of this earth." to anyone. So why do it to your self ?
I was once told that you should never say anything to yourself that you wouldn't say to a child. Treat your inner thoughts like a kid. You wouldn't say those kinds of things to a kid (I hope) so you shouldn't say those things to yourself either.
Hey, this guy Pete Walker's book really helped me to minimize self-attacks like you're describing. The book is called Complex PTSD: From Surviving to Thriving.
This article describes how to combat an overactive inner critic, but I believe his book does a better job. But it's still worth a read.