Angelwings, welcome. That sounds so difficult to get through. I think that you, like all mums who don't get proper support and help from their partners, are a hero. That's my sincere opinion.
You have been given a serious challenge to overcome and you need help. It's good that you're here - I find that writing things down, though it doesn't change the circumstances, somehow makes things "move along" inside oneself.
I don't know what country you're in and you needn't tell us, but there must be resources for mums like yourself. are you in the UK by any chance? I'd be more than happy to do some quick research and find you a place where you can ask for help.
You know better than anyone else what kind of help is needed most urgently - whether it's arranging for someone to houseclean 1-2x a month or babysit or help your older ones with schoolwork or something, or whether the first thing you need to do is get some therapy and/or meds for yourself. If a helpful third party were there right now and gave you one free wish, what would you like them to do?
I am rooting for you.