They (above) may be right OR she may be acting like a typical wayward wife in the first week of withdrawal.
My wife was hesitant to write a no contact letter too....mostly because OM broke it off with her and told her to leave him alone after exposure.
First few weeks are difficult as their sneaky little affair routine is disrupted and all the rationalizations and justifications for having the affair in the first place remain. They mourn the loss of OM and they are overwhelmed with the idea that they are stuck trying to make it work with you.
I like the ideas you expressed about being detached from the upset and anger. Not needing to preach and teach to her anymore. However, if she truly is going "no contact" the more support you can give her with just your detached presence, the better in my opinion. Don't be up her butt chasing her around for conversation because you know it'll just be hateful talk and she's not ready to really listen yet. Just be there - around - in the same house.
My bet is that absent a "no contact" letter - there will end up being "closure contact". The withdrawal is more than she bargained for and it's telling her subconscious that - "wow - you liked him more than you thought". She's likely to fail but maybe not. No contact is more important than a "no contact" letter - but absent the letter white knuckle cold turkey "no contact" is just a game of chicken the wayward usually fails.
One of the best ways to support "no contact" is to take a trip together far far away. Gives the wayward a distraction to think about before and during the trip to help them through the initial tough weeks.
The internet is 90% complaining and entitlement and I hate it because I deserve better!