I've been there! Here is what you need to do:
Stay with him until you are 'done'. This way you will never wonder "what if?". Totally eliminate ALL "what ifs" until the point that you are sick of it. And I mean absolutely, positively, sick of his shit (because that's what it is) and realize that with 6 billion people in the world, your person is out there. Everything happens for a reason and I promise that you will get stronger, not immediately after, but after some time. Also realize that after you leave him, you may rebound with someone (this is natural) BUT IF IT DOESN"T WORK OUT WITH YOUR REBOUND DO NOT RETURN TO YOUR EX!!!!!!!
Dating is all about finding what makes you happy and it's okay if it takes more than one person to show you that. I personally think that you are loveable and you WILL find someone who treats you right ALL THE TIME.
Isn't that something you want for yourself? Now... how bad do you want it?
I'm not good at beating around the bush or sugar-coating things. My responses are never personal vendetta's on your emotional state. It is what it is, whether you choose to accept it or not. <3