I thought that the 2 of you were sharing time with the kids. So, next time you swap kids, mention the concert. Or, tell the kids about the concert when Mom is standing there.
I understand that it's pretty darned difficult for the DB techniques to effect change in her with such limited contact. However, I imagine that it is possible for the change to be pronounced enough to be intriguing when you get together for mediation. By the way, based on some advice in your first thread, I would still stall on setting a date for that. I think MWD wrote in DB that people have been in mediation and the work that they did there helped them to decide not to divorce and to work things out. Additionally, I know that I've changed significantly enough that even my W and I had barely any contact for months, when we got together for an extended period of time, it would shock her.
I'm going to go out on a limb here and suggest that it might be helpful if you also have a social circle that isn't composed of couples. Couples even if they don't have kids in my experience don't engage in the same kinds of activities as single people do. It sounds like your W is engage in more single person type activities though that may just be my impression or channeling from my W. However, it is only a thought.
I don't know jack, but, maybe some of my mad ramblings will be helpful.