Neither one of you can go this alone. Sadly, the addiction is part of the fabric of your relationship. You both need counseling and support if things are going to change. I’m concerned that he is “better” when high. It’s possible that part of what drives the addiction is an undiagnosed or undertreated depression. If that’s the case, it’s important for him to deal directly with the depression as part of his treatment.
I also encourage the two of you to find an addictions counselor who is trained in couples therapy as well. (Not all addictions counselors are.) With 10 years and two children between you, I do think it’s worth taking a few months to see if you can work out a way to keep the family together while your husband explores why his habit is so important to him that he would risk losing his family rather than get into recovery.
You might personally find it helpful to talk to the folks at ProjectKnow.com This is a program that supports families of addicts. They run a 24/7 hotline at 866-531-8636.
Thank you for writing. Having gotten past the anger, you are in a good position to try becoming part of the treatment team.
I wish you well.