Shame it's not quite as simple as that. I've been through it myself, and, although not proud of it, did in the end make an attempt. (and failed )
There are alot of reasons, many of which you wouldn't understand unless you were that person yourself, why someone would want to take their own life.
Yes, I agree, it's very selfish of a person to do that, but sometimes they feel that it's the only way they have of escaping whatever is wrong in thier live. Relationships, drug addictions, loss of family/close freind, loss of job, theft of something important to you, the list goes on.
It's also the whole "What's it like to be dead?" thing that can often stop people doing it. Often feeling that they would if the knew what was on the 'other side'. Just my :twocents: