Originally Posted by constanza
I mean my WAS is clear she's moving on, are we LBS' expected to remain celibate?
You're not expected to do anything. It's up to you whether to stand for keeping your family together or to throw your hands up and move on. Another poster here points out, at one point she wasn't determined to marry you, and then she was. She's determined to move on now, but that's not necessarily a permanent state. There are several success stories here.

Have you decided not to stand? That would affect our advice.

Originally Posted by constanza
A few of you suggested I grab my balls back and refuse, but like May22 says, it's not really in my control.
100% of us recommended against nesting if you want to save your marriage, including May22.

It is under your control to say, "No, I am not leaving." and then not leave.

Originally Posted by constanza
I also can't expect her to respect "house rules"
If you mean "Constanza's Rules", of course not, why would she? Wayfarer put it nicely, "Do you tell a roommate when they can come and go? Do you tell them who they can and can't spend time with? Do you worry about what your roommate ate for dinner? Or who they ate it with? No you don't. Because you're not their keeper, or their parent. "