Some, who seems to be the funniest of people and make everyone laugh, take their own lives 'cause they already run out of happiness for themselves. Perhaps, their jokes are their last hope that the joy they give out might reach them too.
"Yet when I surveyed all that my hands had done and what I had toiled to achieve, everything was meaningless, a chasing after the wind; nothing was gained under the sun."
Ecclesiastes 2:11