I guess my first question is would a letter acknowledging what i have done and showing remorse be an act of validation or pursuit.
Write the letter for yourself to get things off your chest. Then burn it or throw it out or delete it if electronic. DON'T send it. Yes it is a form of pursuit. No it does no good whatsoever. In fact a lot of WAS's will use it as ammo. "See, he admits everything is his fault, I have it right here in writing." Don't buy into her narrative, this isn't all your fault. Do some soul-searching and use this as a growth opportunity. But also be mindful that she is not blameless. She's the one abandoning the M and kicking you out, that is a pretty cold, heartless act.
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I would struggle to demand I move back into the house at this time without causing trauma to the kids.
It's your choice in the end but we have plenty of LBH's here that we counseled to go back home and they didn't, and then later regretted it. You're doing it to try and appease her, but it never works. When the LBS tries to appease the WAS it just makes them look weak and powerless at a time that they need to be asserting themselves. You never should have left to begin with, once you leave it's tough to go back.
When my XW decided she wanted out I told her it wasn't what I wanted but I wasn't going to stand in her way and that I would respect her decision. Later she asked why she was the one that had to leave. I told her "I stand behind the marriage, the kids and our home, I am not leaving no matter what. If you decide to leave then I will not stop you. I would prefer that you stay and work on the marriage, but if leaving is what you want then so be it. But I am not leaving." That's probably not an exact quote as it's been many years ago, but that's the gist of it. There's a book by James Dobson called "Love Must be Tough" that dovetails well with Michele's books. He refers to this as "opening the cage door". WAS's feel trapped in their life and want out. So the LBS should "open the cage door". That doesn't mean kicking her out or moving out yourself, it just means letting her know that you're not tying her down and she can leave whenever she wants if she wants. But it needs to be her choice to make, and it shouldn't be an easy one. She should feel the discomfort of having to find a new place to live and take care of the kids by herself part of the time.
