Susie, one of our hardworking mods, has a comment at the end of every post that says

"It's OK not to be perfect".

Concentrate on the important stuff and be very aware of how you are feeling.
Has everyone eaten a sufficient meal?
It really doesn't matter if all the housework hasn't been done or the million and one jobs haven't been done.

You know when you've reached the stage when you are too tired to be any good to anyone. Sometimes you just have to say "it will have to wait" and go to bed and rest.