@jussomegirl,
He is, most likely, an alcoholic.
You cannot fix him without a ton of help and without him wanting to fix himself.
You will, honestly, be doing him a solid by letting him go so he can hopefully hit rock bottom before he kills someone with his car.
I'm sorry if this is harsh but I dated a guy somewhat like this over 30 years ago. He didn't get any help until he figured out he couldn't lean on me anymore and sweep his problems under the rug.
This guy needs professional help. Love him enough to make it so that his only choice is to get it.