How can one deal with a husband who drinks alcohol and justifies his actions by saying that he is the man of the house, that he cannot refuse his brother's request, that his drinking is for work purposes, and that he controls himself and does no wrong?

Consuming alcohol is forbidden (haram) and considered a major sin (kabirah). It is not permissible for a husband to obey his brother in drinking alcohol because obedience to Allah takes precedence. "Whoever pleases Allah, though it angers people, Allah will suffice him against the people. And whoever angers Allah, though it pleases people, Allah will abandon him to the people." Working late is not an excuse for drinking alcohol. The wife should continue to advise her husband and pray for his guidance.