Oh god Nicki...I feel for you I really do.
I meet myself coming backwards and my two are 15 years appart! But then I also have my big baby in the house
So I know how you feel (thats my darling husband by the way).
Can you drive? I normally sling the baby in the car when I cant cope and go for a long drive out, we go to a farm and I just let her run wild. The dishes will still be there when I get back, as will the playdough on the carpet and the washing in the basket (and probably more besides) but I get cabin feaver if I stay in.
Now you are old hat at this, you know the score (I am talking to myself as much as you) this diet is hard if you are hecticly busy dealing with loads of stress and have no other coping mechanism than food (insert soother of choice) YOU at least are a zumba instructor, so you are working off those slips, you are boosting your feel good chemicals...but it sounds to me, you need a hella break girly!
Now, slap yourself in the chops, look in the mirror and say after me "I deserve to feel good" - go on... then find how you feel good and do it.