Yes, the little darlings can get in the way of any personal plans can't they ?!!
I'm a bit of a lark so what I do in the holidays is run first thing. It's cooler, very peaceful and when I get back before hubby starts work it's still early but the exercise for the day is done - I feel very virtuous. If I didn't like getting up early I'm not sure when I'd run - I'm usually exhausted by the evenings.
It must be really tough if your husband is away all week. Are there any teenage girls living near you who could watch the children for some pennies while you went running ? Or is there a nearby gym with a creche ?
Cheer up, soon you'll be missing their chaos and wishing it was summer again.
Hope you get back on schedule soon.