I'm curious though Starsky, knowing that we won't be having "the talk" when she comes down, are you now suggesting that I go ahead and reach out from the darkness?
It's your call. If it were me, I'd be very uncomfortable if I lost my marriage, and later on my wife said to me "Why didn't you fight for me? For us? WHY DIDN'T YOU TELL ME WHAT I WAS DOING WAS WRONG, AND PUT A STOP TO IT?!"
Now obviously, one can't "put a stop to" what another grown adult does (see my many posts on the difference between "ultimatums" and "boundaries,") but you see my point. Over the years, I have seen many, MANY sitches where a reconciled spouse either says "I'm glad you fought for me!" or a failed marriage spouse says "Why DIDN'T you fight for me?"
You can say "Oh, she knows where I stand on the issue," but I honestly don't think she does. We can't be sure of it, since you two haven't had "The Confront," but I've posted often that I think it's an EXTREMELY unhealthy dynamic when one spouse is cheating, the other spouse KNOWS that they're cheating, and the cheating spouse KNOWS that they know that they're cheating . . . and says/does nothing.
The "devil's advocate" I suppose is that "my darkness IS my "saying/doing something about it," and you can make that case, but I'd be more comfortable if you weren't so far along down your timeline without having had a plainspoken, make-no-mistake confrontation with your wayward wife.