Boundaries are about YOU, and are matters of personal integrity: "I cannot feel safe in a new relationship with you, when you are still in contact with the man with whom you had an affair while we were still married." To me, that seems like a fair boundary, it's Dday's responsibility to communicate it clearly to her if that's indeed how he feels (and it sounds like he has), and it's then up to his xW what she wants to do with that information.
I agree 100% with that...
Me:40 W: 39 T: 17 years M: 15 years S-9 D-6 D final 11/10/2009
"We are all faced with a series of great opportunities brilliantly disguised as insoluble problems."