WELCOME.
i am concerned for your safety! have you called the police on any of his abuse? or when he shows up drunk and banging on your door? that would be a start. also getting a restraining order. you must treat this as a dangerous threat, not something you can manage.
you could also cut off contact. don't listen to his messages, don't call him back. consider an alarm system. take EVERY precaution as you would if this was a stranger.
i am very sorry you are dealing with this. we get it. we know the fear, mixed with the concern for him.