I did sense some history with mum. Sadly his abuse is far far worse and has the potential to be incredibly severe and life limiting. So mums help needs to be contained - she helps but you do not depend on her. As long as she is ok she's around but you limit your time and interactions with her so she is never someone you rely on. Not too much time with her either.
If she's not abusive currently and willing to help go to her but then you'll need to start sorting out getting your own place as soon as you can. In the meantime join any groups for single mums or women about to give birth and after the baby join the NCT etc and go to as many mother and baby things as you can (yes I know it's Covid but do what you can).
I wonder why you have no friends? Could it be that he's prevented that as part of his Steps Every Abuser Follows? They have a manual, pretty much. Mother and baby groups followed by work will fix that anyway.
Fortunately being a young mum has its advantages too. There's nothing to stop you being a good mum, you'll do your growing up as you go along and by the time baby is your age you'll still be young. Get into a decent career and by 40 you'll be on top of the world.
You'll probably meet someone too - but maybe just leave that part till you're confident you can tell the difference between a good one and a bad one. Having an abusive childhood tends to really muddle that one up so there may be a few things you need to deal with in therapy of some sort first.
But as a young mum with one young child I can tell you that really you can do anything you want. You can and will meet someone who will happily be a great step dad, and father to more children if you want.
No one starts their forever career at 18 so though it's extra work it's far from over work wise.
The only thing that will ruin your life is you staying with this POS. That will do it. 100%. As will meeting another POS because you were too scared to be alone.
This man will totally fuck you - financially, emotionally, work wise. He will suck every ounce of hope and ambition and joy from you and when you are nothing he will discard you like a used tissue. He will also totally destroy your child.
It sounds like you get that. Go to the least worst option (mum) and make your plan from there. She at least gave birth to you he's made it clear you are nothing to him.
And read up about abusive controlling men - he will suddenly become mr wonderful to suck you back in. That will last approximately days before he's back to normal. Get all benefits sent to YOU. Ring now.