Also, you know, when people start drinking/drugging very early in life and continue on doing that, they don't really have a chance to mature like other people.
I suspect you find he is immature for 37?
This isn't actually about you, it's about him. He's an addict, he's doing what addicts do - putting drugs before everything else, including you.
I would really recommend reading around the forum here. It's helpful to understand addiction (for you, not for him). You didn't Cause it, can't Control it and can't Cure it (the 3 c's).