I used to know this married couple many years ago, he was a psychologist, she was a doctor.
They had some age different.
She was into sex more then he was so she was "unfaitful" behind his back. He knew about it but "said" she could do it as long as he didn`t have to know about it.
I thought that was a really strange relationship and i felt uncomfortable standing in the middle as she would tell me about her rendez-vous when i wasn`t sure if her husband knew about it?
The husband admitted to me that he had some sexual problems, and the wife also admitted some personal problems when i was on a holiday with her...
One day all three of us sat in her husbands car and he said something about her not doing something right in front of him, like it was ok as long as he didn`t see "it".
They were both smart people, him being a psychologist i assumed he was talking about her affairs, and that was their way to solve a marriage problem.