Yeah like you I just came back from a vacation in Atlantic city and New York.when I was there I just started lazing around and forgetting my diet but its normal since its a vacation. You have to try things that you normally don't eat . tomorrow I'm going to the gym to get back in tracks and start losing the weight in gain there.
It can be hard but doable. It will just require some strenght of mind with the eating. Best advice i can give start with a good clean breakfast. This will temper the urge of just snacking all the great food arround you. And be strict on the menu. Pick whats best for you not always just go for the most delicious :-)