overacting? me or him?

Lately having issues with SO and anger. He just randomly snaps. He gets stressed and frustrated esp when our baby girl is crying and upset- which with her teething has been a lot lately. His yelling and slamming doors/ throwing things around takes me back to bad memories of my child hood with a bipolar dad. I get so upset knowing he is further upsetting our LO that all I can do is focus on how much I don't want my baby going through a similar childhood always walking on eggshells afraid of upsetting my dad- besides constantly listening to my dad scream at my mom and break her down daily. I made a promise that my kids will not have to deal with that. I love my SO very much but this is a major concern for me. I don't eat much a lot of the time because of it... it just makes me so upset. 
He goes through being depressed and hard on himself- thinking he is worthless to pointing the blame back at me for calling him dumb when I just asked if he needed help with something- like our very fussy teething baby. 
I have talked with him about talking to a Dr and get help but he refuses... I am afraid to think sometimes about what our future may become :(