Step back from this and just observe what is going on right now under your nose.
Withdraw and emotionally detach in your head (he won’t even notice) so that you have the emotional space and broad perspective to see what’s happening.
Write up a log of his weed habit over the years alongside how his life has changed with it - is eg when did he start complaining and getting agitated with employers, what has happened to his hobbies, family and friend relationships, what’s happened to his mood.
Then look back at your life - how has it changed - your mood, your workload, your money, your social life etc. How has your life adapted to accommodate his addiction?
Know that he has moved from a functioning addict to one that isn’t functioning anymore.
Pay close attention to how you have felt at different times (let down, confused, disappointed, disrespected, ignored, unheard, frustrated, sad, stressed, angry, hurt?) - and document that. This is the most important part. How are you feeling in this RS?
Then know that this will all just get worse and worse until he has taken your sanity, your joy, your MH, your optimism, your hopes and dreams and eroded your spirit (if he hasn’t already)
Again in your own head and space look at what untangling him from your life would look like. Research options and get some legal advice. Don’t discuss any of this with him until you have you ducks in a row and know what you want to do because you will just trigger a psycho drama.
The worse thing you could do is get in his face and repeatedly demand changes - as he will just turn inwards and resist answer resent you - smoke more and behind your back. If you detach from him emotionally and practically you will stop enabling his addiction because currently you are fuelling it by providing money for food, bills, mortgage - which frees him up to buy weed.
This is the reality shock that he needs. The kindest thing you can do for his life is leave him as this provides an opportunity for him hit rock bottom, be sufficiently uncomfortable to reflect on his life choices and then decide whether he wants to change and grow. He can’t do this when you are propping up his addiction.
You might be in luck OP as if we have a property crash you can “buy him out” which might cost you v little or nothing.
What’s was your childhood like - I am wondering why you are used to people treating you so badly?