@RooRooCooChoo sounds like your weekend is going to be testing! However, it's good practice for when we've finished Bootcamp/when you get to your target.
If you're a mindless grazer, then it sounds to me like you ought to have a small cool box with you, with low carb snacks that you can reach for when you feel the need - e.g. hard-boiled egg, cooked low carb sausage(s), little pot of olives, celery/cucumber slices, cubes of cheese, etc.
Where are you taking the kids for pizza? Do they have anything other than pizza on the menu that you can have? If not, then you'll have to go without I'm afraid
. Eat something before you go so that you're not sitting there, starving hungry, while they tuck in.
Alternatively, if the restaurant you normally go to hasn't anything other than pizza, is there another pizza restaurant you could go to that does? Or another restaurant that the kids would like, that has things you could eat?