Trying to excuse their immorality.
Alcohol abuse is a symptom of unhappiness. It can later turn into a cause, but if the family was so unhappy that they were all drunks, I think the cause was something else.
Or just plain overlooking the crazy careening course of their sin. Alcohol abuse isn’t a problem that presents itself in a vacuum.
The Camelot never came together for these people because it never had a basis in reality. They were all trying to be kings and queens using one another shamelessly. Love as from God didn’t get acknowledged; pride and exploitation as from the devil did.