@Brownowl I can't add anything really to what has been said. Unfortunately it's a situation that you can't sort - only he can. It does sound like he needs some counselling, and perhaps you do, too. My guess is that he won't go for it, though. Enlisting someone, friend or family, who he will listen to is a strategy, as is a GP if you share one. If there are things you want to say that you can't in a conversation, writing them down may work.
One thing that may help you is to realise that it is not up to you. Your husband is a grown man who is, no matter the reason, making choices. For many of us, we spend so much of ourselves trying to make things right for everybody that it becomes so instinctive that we don't even realise we are doing it. Only you know how you feel but it may be that another strategy is to take a step back from trying to solve things and concentrate on yourself and your child. For practical things, ask family or friends for assistance (meals, driving, etc). If you can afford it, maybe get a cleaner for the hardest stuff so that you can focus on you. I'm not telling you what I think you should do, but suggesting other ways.
This is tough stuff. Whether you take action or not, make sure that you are doing what you can handle. Sometimes we feel pressured (often by ourselves) that we should make a stand on something that we are just not ready to deal with. Take care.