I agree with this. At the root, he's a victim, too. I fully empathize how he feels even though how he's managing those feelings are not only unhealthy for him, but also unsafe for those around him.. including his baby.

I'd suggest taking that responsibility off his hands. It's clearly affecting him in a very negative way and he has a wife and child that are likely affected by this. Keep the peace.

His feelings are valid. He needs a lot of therapy to work through this before he'll be of any help to anyone so there's not a lot you can do to change this.

You sound like a strong person and perhaps developed a better relationship with your mother than he did. If you're able to take care of her, great. If not, try and tap into other resources.