It is sad that addiction takes over that part of the brain that would reasonably figure out that this is a downward spiral that will crash some place not good if he doesn't stop.
But he is in denial and continues to use.
What about you? What are your plans for taking care of you in all this?
You can't make him stop, if love could stop an addict then none of us would be here.
But you can stop living in his addiction and begin living in your own recovery and find a better path. I hope you can find your way to doing that soon.
Hugs