Have you made the council aware that you may be adequately housed, but its currently with someone who is abusive to you and suffering with one if the worst mental health conditions out there and it's you and your children taking the brunt of it? If you haven't done this then you need to and you have got to be very clear just how bad it is. I won't Evan say lay it on thick because there's no need, the damage this condition can cause is bad enough there is no need for exaggerating.
Another option is also to contact the person who diagnosed him or any mental health team he is under/been under that are aware of his condition. So long as you were down as his next of kin when he last saw someone from the team, they will be able to release info about him to you. I'd ask them if its possible to write you a supporting letter to confirm your husbands diagnosis, the traits/behaviours this brings, and his refusal to engage in help. I don't know for certain if they can do that without his permission, but they may be able to by keeping his name off the letter. If they can then it's something from a professional that backs up the hellish behaviour you and the kids are having to put up with the longer you remain in that house.
Also the kids school, if they aren't aware, make them aware. Ask teachers/heads of year for a supporting letter to confirm that you've reached out to them just to keep an extra eye on the kids due to what's going on at home, and they should 100% back you up and confirm in writing the wellbeing of the kids is going to become an ongoing issue as long as they are in the same property as him. The more supporting info you can get to take to the council to confirm yourself and the kids are suffering in his presence the better. Also make school aware of your own health issues and you are now worried that the husbands behaviour is causing your flare ups and your worried about reaching a point of struggling with the kids if it carries on. School can then add this into a letter for you and express the obvious concern this will result in for the kids should your health deteriorate, and it will allow them to support you should you start needing it.
Get on at your GP for the same thing. Health deteriorating due to husbands mental health being out of control and the unwillingness to seek help is now putting your health at further risk and therfore your ability to care for children should it continue together worse. They can write a supporting letter for this.
Have you checked what benefits you would be entitled to if you leave?
If you don't want to leave then all I'll say is be prepared for worse if the weed smoking stops. That's usually a very good way to mask and calm alot of the shitty behaviour EUPD people have. I can't see it getting better if he goes and cuts the weed out without professional help to manage his behavior. Would he actually be willing to try therapies if they weren't in a group?
If not,.you've got not hope of change from my experience