Most Helpful Guy
Get legal help. Seriously. You need a lawyer to help you get a restraining order / order of protection against him.
This is a temporary problem with a clear solution. And you do indeed deserve better. Talk to a *trusted* friend and a professional about your own suicidal thoughts.
Seriously: stop asking random people on the Internet for help and take it to people who can actually do something. Do it TODAY.
Most Helpful Girl
Tell him you need a "break" and as soon as he's not looking run and don't look back and if he really gets be have some close (preferably intimidating ) friends at hand. He's toxic for you, and your too good for him and if he wants to go fuck his ex let him good riddance