They are ALWAYS dead set on going ahead with the Divorce, it is their way of controlling the situation. So, don't take the bait. Call her bluff. Let her know that this isn't what you want but you will be forced by your attorney to file for joint custody of the children, therfore lowering her child support and spousal support. You do not plan on leaving the family home, but will be more then happy to help her to move into her own apartment and have half of the furnishings from the family home. That you hope the two of you can work through the Divorce amicably for the sake of the children.
Don't flinch.
There can be no testimony without a test. I am praying to go through this test and come out the other end with a new and better marriage then before.