Despair means hopelessness. When you don't see any ray of hope, all doors seem closed to you, you experience despair. Despair kills all hope inside a human being. To kill the feeling of despair, one needs to move on and accept the reality. Action is the antidote or remedy to kill the feeling of despair and nip it in the bud. In the words of William Cowper, “Absence from whom we love is worse than death; and frustrates hope severer than despair.”
Failure, heartbreak, financial setback etc. are the major causes of despair or hopelessness. In the following quote Niccole Machiavelli discusses one probable reason for despair. Quote verbatim, “A son can bear with equanimity the loss of his father, but the loss of his inheritance may drive him to despair.” People with a positive outlook towards life, never feel hopeless. Despair seeks its prey in pessimists.