I'm pretty surprised at how many people here think that it's a selfish act. Is it selfish is some regards? Yes. I'm not sure that it is in most cases though. Now when we're talking about Budd Dwyer type situations...well...don't even get me started on that disgrace...
Well, I think when a lot of people say it's "selfish" they are not necessarily talking about the person who kills himself. I think, at least to me, that the act is selfish to the family of the loved one. How a person could end their life when they may have a lot of family for support and he is taking himself from his/her family. I worked with someone who killed himself and he had a wife and two children, very sad for his family and very selfish.