advice?

my man's dad is a heavy drinker (drank an 18 pack in less than 24 hours) and its taking an emotionaly toll on my boyfriend and is straining his and my relationship,as his dad get loud and obnoxious and we have to constantly hide the car keys. im getting tired of seeing my boyfriend upset over his dad. is there anything we might be able to do to help him slow down or even stop the drinking? is there an anonymous drinkers group that we can have reach out to help him?