They don't understand, how can they? To the majority of people a glass of wine is a treat and something that is identified with unwinding, you have a different relationship with alcohol and it makes no sense whatsoever to a normal drinker, in fact they will not believe it could possibly be as bad as you are telling them as, to them, it sounds like you are making it up...go and find a recovery program like AA then when you talk to them they will understand you and you won't feel so mis-understood:-)