Feeling left out

Ok so I'm 6 weeks pregnant due 10/4

I'm very excited and happy because we been trying for 5 years with 1 Mc and 1 ectopic that resulting in me losing my right tube. So here I am pregnant and I went for an ultrasound and everything looks great. I just need to be stress free but here's the problem. My husband. All he does is stress me out. 9 years ago he left me for another woman and had a son with her. Just dissed me and our 2 daughters. I forgave him took him back and married his sorry ass thinking shit would change. He treats me like shit. I just wanna be done with him. He's obsessed over his son. Everything is his son this and his son that and im fucking tired of it. The boy has a mother but he can care less about our daughters and our unborn baby. Im JUST wondering if I should leave him or try to work it out. All its doing is making me stressed out and hating him and his son more. I don't know how much more I can take. I take care of his son More than him and the boys mother then last night he told me I'm not in the position to say anything when it comes to his son. We got into a huge argument about it and made me feel like a piece of shit. Like why am I dealing with this? Why did I try to be a good wife and step mother and take care of his son to be told I have no say and what I did for him was in the past? I'm ready to get a divorce and walk out on him. I can be more happier by myself. Any advice ladies?7