Based on that phone call sounds like she is looking to act totally normal and be friendly while we are doing our in-house separation.
Mar, there is an upside to this. I had an "amicable" D with my XW. By that I mean we acted brief, to the point, but normal-ish around each other in our VERY LIMITED interactions. No affection but also no fighting.
You do not need to bend over backwards to be pleasant or nice. I recommend not bending over backwards for anything. However the upside to this approach your W seems to be taking is that if you both play this game you will have fewer scars.
More conversations mean you learn more. See what you learned in this one? It's awful, and I'm so very sorry. But if you simply stop talking you can just part ways without these new pieces of information. Less to haunt you later, less to process and you can spend your energy trying to heal on your own. Fewer chances for her to blow up (and she might blow up if pushed) and say awful, regretful things.
No situation is perfect. But if you decide (and it is your decision) to move-on from your W who is adamant about D and having an OW then this way of being non-confrontational is in my opinion the easiest. It also keeps you from getting in an argument and you saying things you might regret.
I'm not going to lie - my XW was generous in our D. I think part of it was guilt, and honestly I'm not going to get in the way of that. She totally broke my heart and destroyed our life together. BUT I don't think anything I could have said or done once things were in motion would have stopped her. Me quietly accepting it and leaving her alone I think made her feel kindly toward me in a way.
It still hurts like hell, it's still divorce and it's still not what I wanted. But this approach for me was the best path I could have taken. Note that I did not bend to her will in any of this...I just got out of the way.
Something for you to consider, anyway. And this is the reason I still advocate that you spend as little time back in that home as humanly possible for you. Every day is a greater risk for fight, new information or other damage to you. Remove that from your life and I promise you will begin your healing faster and this "active" and soul-punching pain you are in will start to subside a bit. It's still a processes, but you'll be able to catch your breath.
