I've had a few people question me when I order a water or a coke. Sometimes it is a little uncomfortable, but I think it depends on the person who is asking, or the crowd or the atmosphere of the gathering. The first time I stopped drinking altogether, I was still dating a girl who would regularly go out with friends and family to bars or taverns, where it was basically expected to have at least a beer. There were a handful of times when people would ask me why I wasn't drinking, and there was a vaguely awkward atmosphere around the situation. Although, I think I did it to myself by getting a water. I should have ordered a root beer or something more fancy, just to take the attention away from it.