Apparently he is not exactly beating you up, just slapping to be annoying - and it is annoying.
Try smacking him back. See what he does.
you should leave him, it sounds horrible but people do not usually change and if he's calling a lot it means he does not trust you to be alone, those are not the type of people you want to be around. you can do way better and dont feel bad, you will find another person way better
I think you realise you have to leave this guy, it will not change , he is trying to control by his actions , checking on you all the time, no one can live like that ...unless he wants to change and gets help.. but usually they are in denial its them .good luck
You're right that it is abusive. Pretty much classic, all the way from the small beginnings escalating to larger and more constant stuff, to the attempts to control you and track you. If you were to let him, he would pretty soon start trying to cut you off from other people. It's not funny, it's abuse. I only hope you can get away without getting hurt (I mean physically, him hurting you). Call the Domestic Violence Hotline or see some of their materials.
Good luck, nobody deserves to be on the receiving end of this kind of stuff, no matter what the history in the relationship.
ps -- After you're out, get some counseling for yourself. He is at fault here, but there are certainly a lot of people who fall into one relationship after another with similar patterns. Maybe something about his personality that is part of this kind of insecurity and controlling behavior was appealing to you at some level, and if so, the chances of finding it appealing again in someone else are pretty strong. You want to break the chain now.