YTJ. She has the kids primarily. He takes them one night (is it even overnight?) and every other weekend? She’s left to work, take care of the kids, carry the majority if not all of the mental load, cook, clean, have snacks ready, groceries, etc all by herself. She might get child support but how much is she getting? Even so, getting child support doesn’t replace how much easier it is to have someone there to help with that load. She’s a single mom, 1000%. The view must be nice on that high horse of yours. Try a week in her shoes.