When intoxication is taken to the point at which you're losing hold of yourself, it becomes another form of self-relinquishment. And yet many seem to be drawn by a strange attraction to that kind of experience. It doesn't always have to be alcoholic intoxication: inebriation, drugs, sexual abandon, a love of driving at high speeds, dangers generally — all these ways of getting you away from yourself, of getting lost in an experience in which you are no longer in charge of what you think and do, are sought and sometimes even cherished by people. Why is that?
The more you think about it, the more difficult it is to understand: the experience we're talking about comes almost necessarily from an excess and is thus (in a sense) unnatural; the trail of its subject is often indecorous (let's not even mention how the subsequent hangovers feel); in the long run its effects will harm them physiologically, potentially also damaging the physiological basis for their mental capacities, and they can harm them socially, if they drunkenly misbehave and annoy people; it supports and increases temptations from all the other vices, prominently anger (it can lead to brutalization), by lowering the inhibition threshold for giving in to them that comes from shame and other social constraints (not that those are always good for you; at times you may even have to break them deliberately — but not out of drunkenness, of course).
It also carries a risk of becoming addictive. (Most addictions in this area are substance addictions that work on a physiological level, but even so, there's a psychological component to it: you wouldn't expose yourself to addictive substances in the first place if there wasn't some attraction to them that's no yet rooted in their physiological aspect — physiological addiction can explain why it is so hard to get rid of the habit once you're in it, but it can't be the whole story of why people get into it to begin with).
In short, that experience of losing yourself in intoxication confuses conscious perception and lowers control over your reactions, and it brings almost exclusively negative effects in the long run. Again, you might expect this to deter people from overstepping the line — whereas in fact it exerts a magnetic appeal. Some can resist that appeal (in which case we call it moderation and count it among the excellences of character), some can't. But almost everyone can feel it.
(There's a fine distinction we have to make here. It's most easily understood from the example of alcohol: up to a point, it sharpens the senses, gives interactions energy and a bit of an edge, increases the fun level. If overdone, of course, it pulls you away from yourself, and that reverses all these small benefits (which are nice, but still just that: nice, something external) into something genuinely harmful. If, in cases of losing control and relinquishing your grip on yourself, you merely haven't been careful or watchful enough and let yourself slip out of good measure, it's rather a kind of lack of skill than an escape from reality. But we're trying to identify the source of attraction behind the idea of getting away from yourself, and nobody is attracted by an expression of their own perceived lack of skill. Therefore, what exerts that pull of attraction must be in the promised escape from reality rather than in the unnoticed slip out of fine control.)
So what's attractive seems to lie not in the long- and mid-term effects, but in the quality of the feeling itself; it must be something that's contained exclusively in the moment. (Which explains also why it needs some excess: because the feeling must be so strong and sweeping that it eradicates most consideration of future consequences; a slight tipsiness wouldn't achieve that, you need to be heavily drunk.)
But then again, that seems not quite to capture it. It's not really so that the state is overwhelmingly pleasant: most of your sense experiences are blacked out; the detail level of perception decreases, at the same time response time increases; clarity of thinking goes down along with the capacity for articulating yourself; feelings get rougher and less discriminate. It's not really an exquisite feast of the senses: we disengage from sensuality just as much as from reasoning when we try to get away from ourselves.
So it seems that the motivation must lie in a kind of escape from reality, where the reality in question is more the reality of your own person than that of your surroundings: what you try to get away from is you, and perhaps your perceptions and views of the world, but not the world itself (nobody thinks that the world really goes away when you can't look straight at it any more). The whole thing is more about losing yourself than about finding yourself in the experience. (When you return to yourself later on, you're typically empty, not inspired, and you also have the matching bodily feelings during the hangover.)
In what sense is it still you if you're successfully got away from yourself? When you 'lost' yourself in an overpowering experience?
Legally, you are still held responsible for what you do; the grounds for this accountability aren't directly in an attributed responsibility for your actions, but in the fact that you got yourself into that state. Responsibility is inherited here, it's indirectly attached to your actions from a wider context which is still something you have to answer for. It's a case where you're responsible for things that you can't control, but rightly so, for that you can't control your actions is something that you are responsible for by bringing yourself into that state, or by allowing yourself to be brought into it. In the limiting case, where the surrounding context is wider than your entire sphere of control, you're no longer considered a full person in the legal sense anymore; you're no longer responsible, but you also lose any entitlements belonging to that status. Even most morality systems would still hold you responsible (although some moralities based on religion or cult actually assign a high moral status to some out-of-mind experiences, if they seem to convey some spiritual truth).
Thus, if there is still a recognizable legal and moral person in your actions and views while you've lost yourself, the sense in which you are 'away' from yourself can only be ethical: you take a vacation from your character as a person, from the project of making the best out of your possibilities, of living a good life, of becoming the best person you can. It's in this way that you give up yourself, and just as in all the other forms of self-relinquishment, it does go (attractive though it may seem for a moment) against your own best interests.
Life is worth living not because of the moments where we get out of it and let ourselves be swept away, or drowned in uncontrollable feeling. It's worth living because of what we do with our time: what we achieve in the world, contributions we make, insights we have; perhaps some value is also in distinct experiences, in variety, subtlety and nuance; certainly it's worthwhile to connect to others and form relationships. It's true that all of these, although they bring value and beauty into our lives, are inseparably bound up with effort, pains and disappointment. Taking charge and accepting responsibility for them means to accept, and to learn to deal with, these undesirable aspects as well. Trying to escape from that is cheap and cowardly, and not just because you would be timidly trying to get a vacation from those negative aspects — it's also because you de-value, at the same time, the positive values that make life worthwhile. Take care.