A laugh a day

A man standing in front of his grandfathers grave at the local cemetery observes another man sitting in front of a grave and crying.
The man is constatly asking: Why did you leave, why did you this to me?

Touched by his mourning he gets closer and asks him: This must be a big loss for you. Who are you crying for?

The man looks up and says: For the ex-husband of my wife.