When he is home those five days, he may be anxious, irritable etc. Withdrawal from alcohol is a bitch. Most are in a fog and do not know who they are or what they want. Detox doesn't take care of it.
It is my understanding they need protein snacks, cheese and crackers, walnuts and almonds etc. Hopefully he eats breakfast. Just my 2 cents and thoughts.
I just checked Google search for "Diets for alcoholics" Got lots of sites to check.
Caring HUGS to you both.