Help me? I have no idea what to do.

So a little background: WARNING LONG STORY!!

My boyfriend and I were dating for about a year and got pregnant. I had my son and we have been trying to work on things. In the beginning of our relationship, he hacked into my phone, got all my passwords and hacked my apps from his phone. He accused me of talking to other men, which I wasn’t, and made me block every male on my phone. He torture me mentally by talking about suicidal thoughts, demeaning himself, and just being overall a bad person. I should have ended things and trust me I’m paying for it now. I’m hating my life. Anyways, while I was pregnant he was horrific to me. I was in the ER due to stress, he belittled me, I asked a guy friend for advice and he hacked my phone again and saw my guy friend said he missed me because we haven’t talked in a while and he destroyed me over it. His daughter’s mother was threatening me when I did nothing too. Anyways, fast forward, things were a little better after the baby was born. But he keeps bringing things up, accusing me of doing him wrong, stressing me out, and hurting me. But yesterday was the last straw.

So I received a message 6 months ago from my eyelash technician’s brother saying my lashes looked beautiful. I said thank you, he asked for my number and I declined. That was the end of the conversation. We never talked again. I told him about it because I thought he should know since it was nothing. He called me yesterday out of nowhere telling me I’m a lying piece of shit because I’m sending my nudes to this guy, I’m taking him around my son, and I’m getting coffee with him. He says he has conversations of us talking to each other and I’m talking shit about him saying he doesn’t help me and telling the guy my personal information. My boyfriend broke up with me telling me I have one more chance to tell him what’s going on. I’ve done absolutely nothing. I was a mess all day because I was so confused and upset. Fast forward to night when he comes home. He’s telling me he knows I’m cheating I fucked him over I’m a piece of shit for lying and such. After lots of words, it turns out, he was referencing the compliment I got 6 months ago and he made up a whole story in his head that I’ve been living a double life with this other man that I’ve never said more than “thank you” and “no thank you” to. He calling me a lying piece of shit because he made up a story in his own head about me.

I guess my point of posting is what do I do?? He’s clearly severely mentally unwell and dangerous. I want him nowhere near my kids or me. I feel nothing towards him. What do I do though? I also want to get my story out to see if this has happened to anyone else. I’m scared.