This is just my opinion based on a few alcoholics in my life. I think some people find that they like who they are and how they feel when they are drunk. I think it is why they drink. Because they don't like who they are when they are sober. I think that there is an underlying anxiety and strong compulsive tendencies. The alcohol medicates that. Eventually it becomes a physical addiction. I do also think there might be a physiological reaction to alcohol that not everyone has.