You know it is him! Please don't blame yourself. You have been so brave and such a good example to follow...
I really think hellkat is right. Three steps forwrad, two steps back. Today I want this, the next day, he is scared he has made a mistake... The aliens rule.
But you know, I think that your guts were right. You detached and H came back surely and steadily... You saw it, but I don't think H really realised what he was doing. I think he was following the WAS rule of "doing what feels good and not thinking". And ANY encouragement or questions from our side - NO MATTER HOW VALID - made him think about what he was doing... and he got scared and ran away.
I think this rule should be set in stone: Detach and the WAS will follow.
My prediction: He will be back... and this time you will be even more ready...