abuse I need help

Sorry this is pretty long but my life is basically destroyed and I need advice. I started dating a guy I really loved when I was 16, I very quickly got pregnant and decided to keep the baby. soon afterwards the man I thought was perfect started cheating and abusing me. It started as emotional abuse and worked it's way up to physical abuse. The worst it got was when he pinned me against the wall by my throat in front of my toddler who was screaming. A while later I finally plucked up the courage to leave which of course he didn't take well and proceeded to threaten to kill himself so I took him back. I left again a while later but this time he begged for me back a cried and promised he'd change. I believed his lies. He went back to how he used to be and very rarely came home or saw his son. One day I couldn't take it anymore and I finally stood up to him! so he left me and had a new girlfriend with in 3 days. I dedicated my life to ensuring this man had a good life, I loved him cooked his meals, washed his clothes and paid for everything. I decided it was for the best and stayed away from him for a good month and left him and his new girlfriend to enjoy their lives. He never once bothered to see his child once but told everyone it was my fault. He then started to threaten me so I called the police. When he found out I called the police he threatened to kill me if I didn't drop the case. so fearing for my life I did. I went back to staying as far away from him as possible and changed my number. He found it and called me again threatening to kill himself so I went to calm him down and we ended up having sex, I just wanted to make him happy. We slept together another few times despite having a girlfriend. I finally plucked up the courage to cut it off and tell his girlfriend the truth. Big mistake!! She tried to start a fight with me and embarrassed me in college and I had to be escorted out of college by the police. They are now both out to get me and I'm terrified for mine and my child's safety. I can't leave the house to get food or even go to college. I'm terrified and I believe this man or his new girlfriend will kill me. I have no family or friends around me because he ensured all of them left me to make me more vulnerable. I know he'll come for me. I've spoken to the police but there's nothing they can do. Any advice please I don't want me or my child to die.