Then my family says, "But it's a Holiday!" or "But you're on vacation!"
Eerrrr... what? That's what caused the problem to begin with. There is ALWAYS a reason to chow down.
I find that I have to be constantly vigilant and stay with my meal plan, each and every day. I gain 5 lbs by driving past a pizza hut. Whether you're on vacation, or if it's a holiday, or just because it's been a crappy day at work... stick to your guns.
PS: The one day I do indulge, within reason, is the day or two before an event/Triathlon/whatever.