My kids are out of school. I work FT. My W moves, I don't see how the kids stay at the house. They need their mom. As awful as this situation is, they need her as primary caretaker.
As a divorced dad who obtained primary custody, consider that the separation sets up the long-term deal. Courts tend to maintain the status quo. If you divorce, how will you care for you kids over the summer?
a) Work From Home when you can b) Leverage summer enrichment camps (sports, art, stem) c) Part-time nanny, child-care, or au pair d) Full-time nanny or childcare
Assuming you eventually want 50/50 custody, can you take 50/50 custody now and leverage one of those?
Since the money is shared, technically, you're only paying for half these expenses!
Going to Basketball or Little Gym or Minecraft camp for 6 hours and then spending the morning/evening with Dad is arguably better for the kids than always spending full days with Mom. It also may give her a better idea of what the long-term reality is like of splitting the family down the middle.
(Reality may be a bit harder, since she may also have to work to support her home.)
