Copy and Paste Error

A famous motivational speaker said: “Best years of my life were spent in the arms of a woman who was not my wife”.
Audience was in shock & silence.
He added: “she was my mother”.
He got applause & laughter!
A week later, a top manager trained by the motivational speaker tried to crack this very effective joke at home. After a good 3-4 drinks, he said loudly to his wife, in the kitchen: “Best years of my life were spent in the arms of a woman who was not my wife!”
The wife went; “ah!” with shock and rage.
There was a sudden silence!?
Standing for a moment and trying hard to recall the 2nd half of the sentence, he finally blurted out “Forget it; I can’t remember who she was “.
By the time he regained his senses, he was on a hospital bed recovering from burns of boiling water.