I guees least he has admitted it and wants help again. Im the same as your partner and i hate the stuff and i am doing my best to stop. No matter what though now because he is an addict or ex, he is never going to be ok really same with me. So when you went away he probably thought im ok i wont use and hes put himself in a situation were hes gone out with people who use. But i could be wrong.
When did he last use? What is he doing to stop