I'd tell everyone to bring their own drink if possible or to make sure to order a drink if, it's a place you order drinks be careful on getting a punch you just never know if, someone added to it.
Tell them you can't have anything to drink under Dr.'s orders Dr. Bob. Tell them what ever you have to your sobriety is at stake if, it bothers you to tell them you're an alcoholic.
It's no body's damn business why you don't want a drink, just don't drink