It was M's view that my boyfriend was not a serious alcoholic
The gentleman is naive. Your friend is an alcoholic to be sure, and one of the most dangerous kinds at that. He is what is known as a "Periodic"..Iv'e had to deal with dozens of them. He can and does go through long periods of being on the wagon due to employment commitments, social pressures, pressing engagements, etc, but once the pressure is off, BANG!!!...........I don't know how long he's been drinking alcoholicly, but as time goes by the periods of abstinence will grow shorter and shorter and shorter between bouts. However you should know this, it usually takes a few decades for that to happen.
Am I flogging a dead horse?
Yes!