They can't call on their experiences to help them and they can't consider that negative moods can pas away. They can only remember that these moods keep coming back. They are incapable of thinking of alternatives to self-destruction or how their families will feel if they take their own lives. In fact many think that their families will be better off without them. Having everything to live for does not prevent them from killing themselves.
Suicide notes can give some indication of what is going on in the minds of the suicidal.
About one-third of people who die by suicide leave such notes. Most of these notes are loving communications asking for forgiveness and understanding. Some are angry and hateful and are directed at particular people. Others are notes expressing mixed feelings of love and anger. In a few cases the notes are about possessions and funerals.