Fear of Alcohol

Let me get this clear, I have no problems with alcohol as an idea or a problem for me, but I do have a few friends that are alcoholics, or at least I kinda feel that way. I was playing with T, and he got pretty drunk and started getting very argumentative and aggressive, and then afterwards he kinda just goes quiet and starts throwing games. I don’t mind the games part, but it does suck how he goes quiet and wants to kinda verbally fight. That part scares me about alcohol I guess, I can see the dangers of alcoholism.