How do I 27F leave him 33M

My bf and I have been together for almost 3 years. He has 2 kids from a previous relationship and I have 2 kids from a previous relationship. Since we started dating I had a gut feeling he was talking to other women. 2 years into the relationship I found out he was. He promised to never do it again which was a lie. I caught him messaging another woman again. When we had fights he would say things like all women are conniving and that I'm just like his ex's. He would even ask me if I wanted him to cheat on me because he'd have no problem doing it and if I didn't get pregnant then he would. I've tried to leave him many times but every time he would block the door and freak out crying saying sorry and not to leave. He'd even rip my things out of my hand and hold me back. He then would start saying how I'm gonna break his kids hearts especially his daughter because she loves me so much. He'd ask me if I even cared about his kids and their feelings. He'd go on with stopping me from leaving for hours. I eventually would give up trying to leave. I've been so unhappy and he's noticed. I finally told him I'm not happy being with him and that I want to leave. He kept insisting that we are so in love and that I'm just stressed and really don't want to leave. He then brought up his kids hearts being shattered and kept asking if I hated his kids. He then said he will never stop me from leaving and if I wanted to leave I could. He then kept begging me to stay. I shut down. I knew if I tried to grab my stuff and leave he would start to freak out and try so hard to stop me. Do I just pack up all my stuff one day when he isn't home? I do love and care about his kids and feel leaving like that is so wrong but I don't know how else to leave.