PS: Thanx 4 not saying anyone who cuts or other things only wants attention. Then I'd have to scream at you. If someone hurts themselves that badly or attempts to end things permanently, how could that be for attention. I've seen pictures and my friends. They don't do it for attention.
You also have to consider that those that do cut often feel compelled to do so. These people aren't logically considering what they 'should' do or how they 'should' respond. Of course, everything is different. I cut because it took away the emotional pain. I've always liked pain and blood has always been relaxing to me. Even today, though I've stopped cutting due to a promise, I would much rather give myself a cut than sit in bed thinking I'm going crazy and trying to supress myself from screaming...
In the other sense, you also said you want to keep yourself in tact. With the way I was, I hated myself more than anyone. Even now, as I slowly get better, I don't exactly love myself, but I can tolerate myself. But when you hate yourself, it's not like you mind hurting yourself... Regardless, for me, blood and pain also make me happy.
But again, that's just me, and everyone has different reasons for cutting and different feelings that provoke cutting. But the most important thing to remember is that people don't logically choose to do these things, and they come up in severe emotional states. And what thoughts these states provoke are different from person to person.