He is stalking me, help!!!!

LONG POST BUT I AM DESPERATE, PLEASE BE PATIENT WITH ME

Ok, so I have a bit of a situation here and I need some serious advice here. I been single since my boyfriend died 2 years ago. He died at work one day out of the blue leaving me and my 5 year old alone. He was such a great dad and an even better boyfriend. I found out after he died that he planned to propose. I got a lot of support at church, It took me so long to get back up on my feet again and to start to feel like myself again. I never thought I would ever love again. But a guy who I went to high school with started working at the same supermarket as me and we got talking. Caught up on everything in life since we graduated. He had 2 kids with his ex wife and I told him all about my situation. We helped each other I guess and when we caught feelings it sort of took us both by surprise. We had great chemistry and he made me feel like there was a life for me after all especially since I thought my whole life was over. Things went so well and he took real good care of us, filled in the role of the Male figure in my sons life without ever trying to replace his dad. And our kids got on so well together. It was too good to be true. He started to change, he would get angry over the smallest things at me and my son. I couldn't understand why. He would get angry with me depending on who I was talking to or hanging out with. The arguments about petty things started getting worse. It even spilled over into work but I thought that we could make it work, that we were just going through some things like every couple does. So I tried to be understanding and patient. We even discovered that we would be adding to our little family. We couldn't have been happier. Silly, but I thought things might even start to calm down after that. And for a little while, they did. When my morning sickness started to get worse, I left work and went on sick leave, and it helped with the arguments to not see each other so often. Then one night he went out to the club with his friends and took an uber to my apartment after. That is when it all kicked off. He is a nasty drunk and out of nowhere started arguing with me. I don't know how it started. He called me a selfish bitch, I'm useless

He called me all sorts of names, threw shit all around the apartment. Said some horrible things about my family, my sons father, and my friends. I tried to calm him down before he woke my son up, or the neighbour's called the cops. Eventually I convinced him to go home and get some sleep and told him I would talk to him when he woke up and alcohol and God knows what else was fueling his venom was out of his system. I thought once he sobered up, he would realise he was wrong but of course when I woke up the abuse continued. A berage of texts and phone calls flooded my phone all day. Some point he pulled a complete 180 and apologised. At this point I was done, I was exhausted, I told him I wanted a break from us. I needed to think if this is what I wanted still. Then started a month of constant texts after texts after texts, song lyrics, sad gifs pictures, quotes, photos of us together, emails as long as the great wall of China, dropping little presents at my apartment when all I asked was time and to respect my boundaries until i was ready, he will agree for day before it all starts again. He is texting my family and the friends he was complaining about asking if I have said anything about where I'm at with the break. I'm afraid to look at my phone, answer any calls because he has borrowed other phones to try get a hold of me, I dont log into my Twitter, or any other social media. I haven't even been to church. It has been a little over a month and he is showing no signs of letting up any time soon. I don't know what to do anymore, I'm so stressed out. it has painted him in a different light to me What would you girls do in my possition? I have my son and unborn baby to think about in all of this too, I don't know what to do. please help me, obviously I am not going to cut him out completely because this is his baby too, we have a lot of the same friends so cutting him out is impossible.

Would you be able to give someone like that a second chance?