I was thinking about "love" the other day, and in a lot of ways it's like religion in that it exists because we believe it does. Certainly not something empirical, but something most of us believe in. Perhaps for similar reasons we beleive in religion. I also think it's one of our great flaws as humans, we tend to get disillusioned into things more quickly when we provide ourself an excuse to think or act irrationally. I always believed someone drunk still has consciousness of what they're doing, unless they're really smashed of course. Though even if we aren't at that point, the expectations of lost inhibition seems to be the self-fulfilling cause as well.