I was thinking about your comment on bad parenting because she sits on the other side of the hall. You say you see it as controlling but you let yourself be controlled by moving yourself, why?
You are there for your kids, they will know that wherever you sit. You are still looking at her and what she does rather than doing what you want! You were doing well a few weeks back but as you have said you have back peddled. I get it and understand it, it's easy to do especially when you are looking for anything, any scrap that she might throw out. Work on getting back to the Surfer of a few weeks ago.
My W has done similar things but I do what I want, we were meeting up to go to our sons soccer tournament. She arrived and beckoned with her head for me to come over to her, I didn't, I stood my ground and if she had something important to say she knew where I was. She came over to me and started speaking German, I know what she said but just ignored it with a smile on my face and spoke English to her. It's her ego in overdrive and her look at me attitude. The whole tournament, I played with my son and had no interest in going over to her. She became the one lingering or moving towards me.