She obviously hasn't hit him with the real question or else the LW wouldn't have needed to bother asking Prudence. "She asked him and he didn't understand" doesn't count - after 3 years it's difficult to feel sorry for her if he hasn't moved on it.

That said, why is it incumbent on him to tell her that he wants status quo? I can't think of any situation where I've felt the need to clarify "Hey, I think things are great the way they are now." If she wants to get married, she needs to bring it up. This isn't 1940 any more, she doesn't need to wait for the Sadie Hawkins dance to ask him.