Al Anon and Nar Anon meetings would help you better understand things.
Though he may not be using, he may be carrying all the outward signs of someone who does us.
ACOA meetings for him would help him deal with his issues.
You can't change him. He needs to seek change for himself.
Counselor meetings.
You could go as a couple and talk things out or go as an individual and grow as you are able.
You can't change him. You can only change yourself.