Not just a little sub-par, but totally outside the solar system.
What planet is Dr. Rosie living on that she would advise a bride who caught her groom in the act with his ex-wife at their wedding reception to stay married to that total "Donkey's head covering"?
Definitely not earth.
Well, she's a sex councillor. And many of them (not all, but an unfortunate subsection) are of the impression that
no sex is ever "bad" or "immoral". (I recall seeing one on TV going on about how if your mate is having sex with other people, you should apologize to them for not giving them what they clearly need. Not the mention the one who felt so sorry for Jeffrey Dahmer - society is so
intolerant of necrophiles....)
So, if what the man did cannot be defined as "bad", merely as some sort of annoyance, then the wife just needs to "negotiate" an "understanding", so perhaps he avoids sleeping with her sister on their first anniversary.