Hi, Rock, I just wanted to chime in my two cents to your questions.
First, about the changes...if she brings up the past about you not communicating or taking her for granted acknowledge that your part in this, "I recognized that I needed to work on communicating with you in a way that you were being heard. I also realize that at times I took you for granted." (This would be taking ownership of some of things she felt contributed to the current situation).
-OR-
"I understand that you feel my communication was frustrating for you and that you felt I took you for granted (validating her feelings w/o agreeing or disagreeing).
Then I would add, "I am working on my own growth in these areas."
I guarentee she WILL notice them after consistent long-term changes are made.
As far as a response to your "showing validation and detachment," ...When she talks to you stop what you are doing, look her in the eyes, and LISTEN. Just by doing this alone you are validating that what she has to say is important. You don't even always need to respond.
But again, you can repeat what she's said using her words to demonstrate that you've heard her (but not necessarily agreeing with her).
Detaching has to do with your lack of emotional response to her no matter what she says or does. This one is tricky b/c it takes a lot of "fake it 'til you make it" doing.
One who is detached would not take the bait when she tries to engage you in an argument or brings up a controversial topic. I think of detachment like talking with someone you work with (but are not close to)--respectfully & politely and definitely not with any emotions connected to your conversations.
Finally, I don't agree w the whole pushing for "buying her out of the house" or formalizing the child custody at this point. It seems like A LOT of pressure to her when she hasn't even been given time and space to change her mind!
Just my two cents!
M- 18 T-21 S-14,11 & 10 BD 6-18-2012 (OW-EA) H moved out 11-3-2012 10-5-13 Me- I want a divorce. I want to move on w my life. 11-25-13 Jointly filed.