@emhill123 my heart is breaking for you. I've been in exactly the same position, except I stayed and kept trying to get him to change. I can tell you now that he didn't and it wore me out and destroyed the love that I had for him. Our kids also started smoking weed when they were teenagers (they stole it from his stash on occasion they told me).
My ex DH also had a bad childhood and my heart bled for him. But I can see now that I was enabling him, I mothered him basically. I took care of the majority of the adulting. Yes he did the shopping and cooked etc, but only if I told him what to buy, what to cook etc.
Please please leave him. This is what I wish I could tell my younger self. You deserve better and so does your DD.
He may stop smoking if you leave him and try and persuade you that he's changed, mine did, and after 8 months of living apart, I took him back and gradually he started to fall back into his old ways. It then took me another 2 years to find the strength to kick him out again.
A part of me feels awful for abandoning him, but I just reached a point where I could no longer do it, I had to put my own mental health first. It sounds like you are at that point too and I want to add to the voices on here reassuring you it is ok to put yourself first, no one else is going to are they?!
He needs to take responsibility for his own health, and if he can't even take his meds then why the hell should you destroy your life for him just because you're married???