Someday, he might understand all the damage he has done but that day is probably a long way off.
You say he crossed a boundry. He used drugs in the house. What are you prepared to do about it? Nothing changes if nothing changes. He won't change. He's not ready to change. People who don't think they have a problem seldom do. But your choices are NOT limited. You have more options than you think.
Do you have it in you to consult with an attorney to find out what your rights are in the event you decide you're really ready to do something? If you aren't ready to act now, at least you can tuck the information away and make a plan for yourself.
I'm not saying any of this is easy. It isn't. I left an exah too...with my son in tow. It was the hardest and yet the easiest decision I ever made. When I realized that my exah was slowly taking me under with him, I realized that I HAD to do it...It was a matter of survival...not so much choice.
You are NOT trapped.
You are a child of God. You deserve to live in the light...with diginity and peace. And so do your kids. You CAN do this...You can do anything you want. All it takes is one step in the right direction...
Sending hugs, light and love...