Wasn’t aware it was a popular ‘line’ as you put it but I don’t buy that she knew ‘nothing’. And I stand by that women “know” when something is amiss.
You can stand by that statement as long as you like. Many a wife has found out years later about something they didn’t have a clue about.
What I object to here, is the idea the wife is guilty by association. We don’t know all the facts yet. In time it may become clear she was covering for him. And then it will appropriate to take her to task too.
In time it may become clear this guy was leading a double life, and she didn’t know. We will see.