He lasted 12 weeks before he called you saying he missed you too much and wanted to leave.... My AH lasted 4 days before calling me saying he missed me too much and wanted to leave, and he had started arguing with other people there too. He said "arguing". Who knows what really happened. He didn't miss me too much. First thing he did when he got home is drug himself. No "hi". Just straight to drugs. The problem with thinking he was perfect sober -- and I get this, I really do because I think this about my (x)AH too -- is that this is not who they are. The reality of the situation is that you are not dealing with a sober person, you are dealing with a person who will always have this addiction. Always. Even if they go into recovery, they will have to manage it, and they can and usually do relapse.
Puzzledheart has a good suggestion. Change his name to "don't do it" Lol!