Forget the past and move on..

A wise man once sat in the audience and cracked a joke. All of them laughed like crazy.

After a moment he cracked the same joke again and a little less people laughed this time. He cracked the same joke one again and very few laughed this time. When there was no laughter in the crowd, he smiled and said "When you can't laugh on the same joke again and again and again, then why do you keep crying over the same thing over and over again. 

"Forget the past and move on"