Unless you can guarentee you will not be tied to this man (as in, no contact or involvement whatsoever) I'd abort. If only for your sanity
Slightly different as I can't speak to how your guy has been abusive to you... but My biological dad was evil. Pure evil. My mum ran to a different part of the UK when I was 5 due to it. She was forced to let him have access due to different damn laws :/ .
One of my strongest memories is age 6 screaming and crying not to get dressed to go with him, whilst my mum yelled and cried that I had to. It was awful.
Re manipulation/spite .... When I had to go for overnights she would have frequent harrasing phone calls at midnight ect telling her I was ill or hurt or in pain (knowing she couldn't drive and he was across the border with me! But i was actually fine and asleep!) There was also the threat hanging over that if something did happen to me, he would fight her judgment on any medical decisions. I could go abroad at 13 with school, only cause he died. If he hadn't dropped dead I wouldn't have been allowed foreign travel til 18.
At one point he made threats to take me away for good, and kill anyone who got i his way. (mum was in court that day) and my cousin with a police escort had to take me out of school because police + the bloody courts knew he was a monster and it was a legit threat. still insisted on 50/50 though -.- as he hadn't abused me.
Eventually we moved to a different part of the UK and thank god the devil got bored or too busy with drugs and booze and didn't look for us. When I was 12. He finally died. A year later my mum was sectioned after having a breakdown. 14 years later she is still on medication, top psychologists have said she's so traumatised it's hard to do any work with her.
The only safety my mum had was when he died. Heck. The only safety I had was the relief he was dead and wouldn't be able to kill my mum now.
I know she's glad to have me as I'm what made her leave eventually....
I would honestly rather abort if my relationship turned abusive. Everything legally ect is so damn hard to prove especially with the rigid emphasis on 50/50. It wouldn't be worth my sanity to deal with being tied to someone like that.
Good luck with whatever you decide.