It seems apparent that the mother needs to be earning additional family income. The kids seem to be doing well, they are evidently old enough to pitch in with the home chores including cooking, and it would not hurt for them to have part-time jobs and kick in with household funds, too.
The mother may prefer to stay at home and be there for her kids -I totally get that (and feel the same way), but clearly this derech is not working for them financially. Perhaps she can get an evening job for a few hours, if not full time by day, when her husband is already home and can be there for the kids as she has been. I have been there, and I know it is not easy.