Sleeping through, HAHAhahaha!!
If it makes you feel any better I've had some chips tonight too, and some king prawn fried rice.
Other than that I've been quite good though.
You sound like a very lovely friend Chippy.
I agree that there's not much you can do about what they feed you while you're there. It's a PITA that something always crops up when you're feeling galvanized to eat better that throws a spanner in the works.
Any chance that part of your helping out at your friends could involve cooking dinner? Then you could decide what was on the menu. 
It sounds like you are doing the best you can under the circumstances, well done for resisting the crisps & biccies & for not binging!
Playing with the kids in the park is definately exercise in my book too! 
DS3 has been a smiley, giggling bundle of joy today, according to DH. That would be because he slept well ( not through though ) last night. I'm off to do some stuff ( housework, yawn ), I'll be back on here around midnight.