A straight-laced man is sitting at the bar, buying rounds of whiskey and obviously having a good time.
His good friend is walking past the bar and sees him in the window, and comes inside.
"Jim," says the shocked friend, "What are you doing? I've known you for over fifteen years, and I've never seen you take a drink before. What's going on?"
Without even taking his eyes off his newly filled shot glass, the man replies, "My wife just ran off with my best friend."
"But," says the other man, "I'm your best friend!"
The man pats his old friend on the back and says, "Not anymore!"