I have no experience being in an abusive relationship but honestly I think your "he's a nice guy deep down" mindset is a huge problem. You need to realize that no matter how many good qualities he has, they do not make up for the fact that he abuses and manipulates you. If he truly loved you and he was truly good, he would not do such horrible things.

I know when you fall in love with someone (even if it's just platonic) all you can do is focus on the good. Try to stop yourself from dismissing the bad things he does. Make a list, never forget it. When you find yourself thinking of all the good things remind yourself of all the bad.

Personally I suggest you break up with him ASAP. If you fear he will abuse you break up over the phone if you must. Safety must alway come first and honestly he doesn't sound like someone who deserves a face to face break up anyways. Breaking up in a public place is also a safe option but he could make a huge embarrassing scene so it's up to you.

Also stay with a friend or family member for a while if he gets super aggressive. Don't stay alone somewhere where he would know to find you or if you do at least keep a self defense weapon and keep the windows and doors locked. Might sound extreme but there are so many stories of women getting beaten up or kill by their ex-boyfriends and husbands so it's best to be safe.

Personally I think it's best if you just distance yourself from him. If he is abusive and manipulative as a boyfriend he probably won't be any better as a friend