A man is almost about to die

As he lay on his deathbed, the man confided to his wife, "I cannot die without telling you the truth. I cheated on you throughout our whole marriage. All those nights when I told you I was working late, I was with other women. And not just one woman either, but I've slept with dozens of them."

His wife looked at him calmly and said, "Why do you think I gave you the poison?"