Even most famous people in the world have tried or have at least thought of doing so. Just now I read an article by Chetan Bhagat which stated that he had attempted a suicide. A couple of weeks back I had read about Kailash Kher, now a famous singer, that he had decided to end his life if music did not work for him. The list can go on.
Why does a person think of taking such extreme step can be understood only if you ever thought of doing something like that in your life.
So let me tell you the reason : It is this feeling of being unwanted, dissatisfaction and loneliness. No one creates all this on his own in most of the cases. The most outgoing person can have this feeling and the decision of ending one's life can a matter of seconds. If given more time and support the person understands the importance of life and uselessness of ending it.
I would not preach that God gave you life and he wants you to be happy. I want you to find out the sadness behind the smiles you see and help, show support and make that smile real.
I can say all this because I have been through all this and I thank my saviours for being there for me.
All one needs to realize is life is beautiful.