Advice....?!

So I've decided the best thing for me & the father of my child to do is seperate. After about 9-10 months of living together and almost a year of being together. And me being 25 weeks pregnant, also him being in my 15 month Olds life since he was 5 months. The arguments are non stop, I feel like there's no respect, we've both gotten physical since I've been pregnant. I've left a few time but everytime I give n and come back either because I feel bad doing this to my kids or he acts suicidal or like he's gonna just ruin his life....I do love him but since I've been pregnant his attitude/personality has changed. He legit is bipolar and can't be talked to, and can't understand why I ctfu the way I do for some odd reason. I'm stressed to the max. No job and will have to go back to live with my mom (I'm 20 & he's 26 btw) & apply for low in come housing and find a job in the mean time to support my kids. I've done everything physically possible but it doesn't change. He can't understand anything right now except that he doesn't want me to leave him....but I'm moving all of our stuff tomorrow while he's at work.... he doesn't know but I feel like he should but I don't need more stress. My unborn has absolutely nothing and my son can't fit anything but winter clothes. And of course it seems like I'm the only one willing to break my back to provide for them at 6 months pregnant....ugh. it's so much more but it waaaaay too much to explain.