I've read in some posts that the AP is an addiction or a form of escape or both. It has been compared to being a workaholic at times, too. From what you posted I'm concerned that his new A is the job. He's avoiding something, which could be problems in the M or taking a long look at himself.
Is he in IC? I read your back story and this seems to be a pattern for him, which might mean he needs to take some time to gain some insight into why he does this...drunk or not.
What else is he doing for R? Is there NC, transparency and remorse?