The fact that he is discussing/negotiating cutting down their alcohol intake suggest that he is trying to control it, so he knows he has a problem. A 'casual' drinker wouldnt do that, they wouldnt need to 'control' it, they would just stop - no big deal.
I agree, its good to shrug, better than getting involved in that 'game':
You: You said yesterday you would only have one.
AH: Well I felt like another, I had a bad day, tomorrow I will only have one.
You: You said yesterday you would only have one.
AH: Well I felt like another, I had a bad day, tomorrow I will only have one.
Cont.......