Welcome to Sober Recovery. So sorry for what brings you here.
I quit pot and it wasn't long before my drinking got out of hand. As a recovering drunk I have only two pieces of advice:
1) He won't recovery until he's ready.
2) You can only fix you.
Suggest you visit our friends and family section. Lot of folks there who have gone through or are going through exactly what you are:
Friends and Family of Alcoholics - SoberRecovery : Alcoholism Drug Addiction Help and Information