The Single Girl's Guide to Home Ownership

I don’t know if any of you saw David Letterman’s show last night, or like me, saw this clip this morning, but am I the only one who is seriously disturbed by the fact that the audience was laughing? I mean, I got the feeling he was being about as serious as a comedian (who naturally have a tendency to use humor as a defense mechanism) could be. The situation is sad/humiliating/wrong and by no means a laughing matter. He’s married, he has a child, and he just admitted to some very inappropriate behavior. What is wrong with people?