Hey BigSis...
Well, I must admit that I thought the exact same thing as well... until I hooked up with ex-ABF. In fact, ex-ABF did have a problem with meth, and despite every inclination in my head... he has been able to remove all of that from his life. The problem? Marijuana. He can't let go.
Perhaps he can't let go for the same reasons we can't - that he doesn't think it is "that big of a deal". But you know, that's the same thought that alcoholics have, too... that since something is somewhat "socially acceptable" that it can't be all that bad.
I know what you mean - it is very hard to accept.
Something else I thought about when I read your post... you know... I always thought that if ABF would just quit using, everything would be perfect. The world would just come together, and we'd almost literally ride off into the sunset and toward our futures... which I hadn't quite set out in stone, but had something to do with having these ridiculously beautiful and of course absolutely genius children... great, warm little house with a picket fence... and our dog (at least that was a reality for awhile)... and that everyone would be so darned happy for us.
Thing was... even when ABF was pretty obviously clean and sober... he still lied. He still manipulated. He was still very selfish. I don't know if that is learned behavior, over the years... or if that is just the way that he is.
For me... it was kind of a breaking point. To this very day, friends and family can't understand why I couldn't find it within myself to break up with the man when he was arrested... but that it has actually come quite easily now that I have the realization that he is sober and he is still not the man that I want to spend the rest of my life with. They just don't understand. That's okay - I wouldn't if I were them, either. Thing is... I was willing to see what happened if he got help... if he really committed himself to hard work and rehabilitation... to working this thing out. He got sober, but he didn't do any of those things. Once I realized that he was never going to work that hard to keep me and to keep the important things in our life... suddenly, it all seemed like a no-brainer.
That's just my experience. This man that you are with... he may not be like my ex-ABF. But I just wanted to share my own experience.
I hope you're feeling better.