Newbie Error- LRT too Soon- help!

[Bart42]

So the latest:
Decided I would take some time and GAL, interview some lawyers, and figure out what I wanted the rest of my life with my kids to look like, as those were the only things I could control. Didn’t get that far as I also decided to lay down a boundary that our household money would not be used to support her A. So I asked that she set up her own bank account and arrange for direct deposit and we could work on an allocation of family/household expenses to be paid by each of us. W doesn’t want separate accounts because “it doesn’t bring us closer together” (cake eater!) and naturally, because “there is no A- it’s over.”
Conversation was civil, I was short and simply restated my position that I was not interested in rehashing old arguments and that I am unwilling to live in an open marriage. Said I didn’t want to take unilateral action and initiate a divorce, but will have no choice if we can’t agree to work together. Conversation ended in an “agreement” to see a mediator to work on a formal separation. That was yesterday.
W calls today to tell me how mediation is a waste of time and money because neither one of us wants the marriage to end and there is no A for her to end. Didn’t bite and told her we either agree to do this together or we fight about it and give our money to lawyers. Now she’s delaying by claiming she can’t make the date I set up with a mediator work with her schedule. I’ll keep asking W daily for dates with the mediator and use this week to sit down with a few attorneys. Will also try to go dark, but the kids and one house are complicating factors.
Knowing her personality, even in the unlikely even she actually ends the A, she’s unlikely to ever admit it continued in the first place, making it unlikely we will avoid separation/divorce because there will never be that honest discussion from which to move forward. But without truth, some remorse, and a solid base of transparency (coupled with no contact, unlocked phone, etc.) I don’t think I will ever be able to move on- but that’s her choice. It will be a shame, because I truly believe in her heart she is conflicted and doesn’t know whether to go with me or OM/divorce, but I also don’t have confidence she will agree to open herself up to me to the extent required to save the M because she is such a private person and doesn’t really trust anybody but herself ion the end of the day.
In the meantime, I’m thinking about me, my kids, and GAL (but that’s hard to do).