I just need advice, help. I'm not sure where to start...

My husband and I had a huge fight today. I'm 7 weeks pregnant. We have been through alot because we had an on and off relationship through high school and he hurt me alot. He was very untrue and dishonest majority of our relationship but he was my first and I loved him. He was not there for our first child. He came into my life when I was 6 months pregnant with our second. (We'd break up Everytime I got pregnant...) Well things were great. A few months later I found out he had texted girls behind my back and told his friends I was a bitch and a bunch of other nasty things. One of the texts he had said he regretted purposing and told his friend not to make the same mistake he did... He was also giving his friend advice on how to hide Snapchat better so he didn't get caught again. I packed all my stuff and was going to leave... I didn't end up leaving. He persuaded me to stay and said he loved me. We had two kids and I didn't know how to leave. A year later we decided to get married. It's been 6 months since we got married and things are getting bad again. He is disrespectful and rude. I have no idea if he has been dishonest again but he's just so unhappy with his life. He has no patience for me or the kids and is always stressed out about nothing. He takes everything out on me. I do my best to be a good wife and mother but it only goes so far. He's always accusing me of talking to other guys, etc. I'm a stay at home mom because he wants me to be... I stay home with the kids and don't talk to anyone aside from my mom! This isn't everything, I tried to keep it short. What do I do? I love him and and we have been together so long but I don't want to do this anymore. I can't stand to see my kids be put through another fight. He told me he'd do everything he can to make it hard on me when we split up if we ever do.