Friendship among Women:
A woman didn't come home one night.  The next morning
she told her husband that she had slept over at a
friend's house.  The man called his wife's 10 best
friends.  None of them knew anything about it.

Friendship among Men:
A man didn't come home one night.  The next morning he
told his wife that he had slept over at a friend's
house. The woman called her husband's 10 best friends,
eight of which confirmed that he had slept over, and
two said that he was still there