Yeah I have always noticed that alcohol just brings the arsehole out of people, rather than put it in.
I think it really comes down to, at least with some people, they believe that being drunk gives them the excuse to actually speak their mind. One night they're pissed out of their mind, telling you how much of a dick they think you are, which is probably true. The next morning they have the out of "Oh I didn't mean that, I was just drunk" when in reality there's a lot of truth to it and they're frankly just too cowardly to healthily confront their negative feelings with people. <--- Of course this all speculation, just a thought really.
I remember on my 19th birthday, dropped some acid, had a free house and all my closest friends were just sort of hanging around chilling with me.
I just have this distinct memory, of being outside, and this friend of mine was just being such a dick as he was pissed out of his mind, but he was always that way but the alcohol made it worse, and the LSD on my end made it just extremely obvious and irritating as I didn't understand why he felt the need to be such a douchey prick.
Of course, ultimately I found it to be his problem and not mine and just tried to avoid him. That was until he tried cutting a cigarette with my kitchen blender wand, you can guess which of his bodily fluids ended up all over my kitchen/carpet. Brr, that was really annoying.
Eventually he dropped off the face of the Earth, haven't seen him since October, although his negativity had the tendency to bring my buzz down so to speak, I definitely miss the guy.