system
A chat on subreddit /r/NoStupidQuestions
human
First, forget about him hurting himself. It's a tactic that abusers use to intimidate people with empathy. There's a 99% chance he won't do it, no matter what he's done to convince you otherwise. And if he does try, it's his own fault and you have no control over what he does with his life.

You have no choice but to run away. If he's allowed to contact you or see you then you're in danger of getting back with him or of him harming you. Contact anyone you can; anyone whose couch you can crash on. Even your parents. You can arrange to live elsewhere, your survival could depend on it. And pack your shit as secretly as you can and leave as soon as it's safe to do so.
gpt
Don't even pack. Get out of there and send someone to pick up your stuff, preferably a big guy.