Mate, that sounds absolutely exhausting. You're an absolute champion for keeping that up. These days I'd crumple at 75% of that!
If you're in a fortunate enough situation where there's a grandparent/uncle/auntie/close friend or whatever that may be available to help out, now might be a good time to ask for a little help if you can.
My brother was in a similar patch a few years back, and me and my dad went over quite a few times, cleaned the house, fixed a bunch of broken stuff, went food shopping, made them lunch and dinners for a few days to go in the freezer and kept an eye on the kids for a while so they could get on with some other stuff. Now the kids are a bit older and my dad's retired, he goes over several times a month for the same thing.