Divorce advice

I’ve been with my husband for 7 years and married for 3. We have a 3 and 1 year old and I’m pregnant AGAIN! Unfortunately our relationship isn’t working out he controls his drinking for a few months and then falls off the wagon again. His dad used to bear his mom and he was a heavy heavy drinker. He still drinks now Friday-Sunday from sun up to sun down. He always tells my husband not to let himself get controlled by me and that he’s the man this and that. I helped him get out of drugs but the alcohol is the one thing he keeps falling back on and it’s always ok in the beginning of him drinking and then shit hits the fan. He’ll get angry and go off for something as simple as me asking him to turn the tv down a bit. I’m very aware of this relationship not being healthy and I’m already going through hell with being away from him because when he’s sober he’s a great father and husband our payments are always done on time we have a nice truck an RV and food in our kitchen all the time. But the alcohol messes him up. It’s been 3 years of the same thing over and over. I love him to death but I’m a mom before anything. I’m just scared he’ll completely fall off the wagon and it will break my heart to take my kids away from him completely. Has anyone gone through something like this? I just need advice 😞