Imagine thinking that you are worthless, then imagine the emptiness you would feel. Depression would come and sadness too, and everything you did, would never seem real.
You criticize everyone and even yourself, because a perfect world it should be. Your outlook on life is negative, and the pain is to deep to see.
The pity you feel, is only for you, and your always wondering why. Suicide is one way to go, if you really do want to die.
Imagining this is hard I know, but people really live this way. It's a lonely existence and all to real, but it's how they get through the day.