Hi Luna...
Welcome to SR. I'm glad you found this site. Its been such a blessing to me. I didn't know much about addiction either until my exah (ex-addicted-husband) decided to give heroin a try about 4 years into our marriage. The best part about SR (aside from how much I've learned here) is knowing that I'm not alone in this struggle.
From my own experience, I'd be willing to bet that you only know a small fraction of what your AH has done in terms of drugs. For every incident you know about, there are probably ten more that you don't. Thats the scary part.
After years of trying to 'help' my exah, I realized that nothing I said or did was going to make one bit of difference. Nothing. I had tried everything up to that point to make my exah see how his addiction was hurting him, me, our marriage, and our son but I might as well have been talking to a brick wall. You can't convince your AH that he has a problem. You just can't. The only thing you can do is take steps to make sure that the consequences of his addiction fall squarely on HIM and not you.
Welcome again to SR...
I hope you stick around a let us get to know you better. This is a wonderful place to work on YOUR recovery.