I saw your other post and I've been thinking about it this morning, and honestly I think you need to just let this unfold as she's planning it.
Crazy, right? Except maybe not.
You've been working on you. You've been working on becoming the best version of you. You should do that anyway - for yourself....but that is your primary focus.
If she moves out, that is the first step towards the fantasy starting to crumble. Until now, she and OW have had to sneak around. Until now, they've only seen each other at their best - adrenaline has been pumping, they've gotten themselves all dolled up....If they move in together, several things will start to happen:
1) They won't be hiding their relationship anymore. That means friends, family and neighbors are going to be in the loop for both of them. That means they're going to have to face A LOT of people with the fact that they've walked out on their families.
1a - If you take the stance that you are NOT going to divorce her right away and you are NOT going to date other people, who looks like the awesome stand up guy? That's right - you do.
Do not beat up the guy. Do not go to their apartment. Do not make threats by text or email. This is detachment for real now.
1b - If you take that stance, however, you've got some serious boundaries to set. This is going to be tricky for you. It's going to feel like you're pushing her away. It's going to feel counterintuitive. You'll have to trust all the vets on this one - but I believe that it works.
2) Their masks with one another start to slip. Now she gets to see him in the morning with his bad breath and when he takes his morning constitutional. She gets to see what happens when he gets texts about his kids. She gets to see him at the end of a really crappy day of work. They get to argue about bills, and how hard it is to pay them when they each have to contribute back to the families that they left behind.
Their magic relationship becomes less magic and more real. The statistics of these relationships lasting are incredibly, incredibly low. Basically - they don't have a chance.
3) With the super-detachment, you really get to work on you. I believe that this is easier. You can figure out the places you need to work on the most. I don't know you except through here, but my guess would be that you might want to work on less dependent relationships, maybe issues of abandonment, potentially anxiety....I'm just guessing. You and your IC can figure that out. If you don't have one yet - REALLY get one now.
4) Lastly - if she does leave, it's time to really look after the kids. Make an appointment with their schools to tell them that things at home are a little crazy right now. Schools have counselors who can keep their eye on the kids and will work with the teachers as well. You would do this for your kids if their mother had died, and frankly - this type of situation is similarly tricky for kids. The school may have a good recommendation for counselors for the kids, too.
Hang in there. It sounds like your road is getting bumpy. It's time for you to hunker down and really take care of yourself. You can't force your wife to do her journey the way you want her to. You're going to have to make some hard choices that go against the way you've done things before. Patience, strength, and courage, my friend.
