You can't do a thing about his refusal to move on, but it's healthiest for you to make a clean end to the relationship. Take all of your things, make sure he doesn't have access to any of your accounts and such, block him on social media and on your phone, and don't give him your new address. If he tracks you down, it's stalking. Develop and maintain firm boundaries.

Be vague..you found another place, this isn't working out for me, my life is taking a different direction, etc., then move out, or ask him to move.

Don't argue, or even discuss it with him. Take your stuff and vanish, delete him from social media, block him if he stalks you online, find new friends and places to hang out, etc.
If friends ask you why you broke up, just keep saying that it wasn't working out, and immediately change the subject.

Solid boundaries are very important.

I've screwed up every relationship I've ever been in, so my advise is to.do everything the opposite of what I did.

If you can get physical distance between you it would force him to move on. If not, be ready for a restraining order. Since you describe it is bad, rather than just not working I am thinking there is potential for violence. Don't get careless.