The thing about wagons is that once you fall off, you can jump right back on them. Don't beat yourself up. Just start again. You cannot change what you did last week, yesterday, or an hour ago. Dust yourself off and commit your energies to tomorrow.
I go off plan when I'm out of town (which is about 2 weekends a month). I give myself a line in the sand that I will not cross. When I go to tailgates (I'm a big college football fan), I limit myself to one beer or drink. I don't ever have soda (as much as I used to drink the stuff). I drink water during the game.
I also find that I do better when I weigh myself every single morning. I know that weight can vary significantly, but it keeps me honest. If I was bad and had a chocolate bar and carbs, the next morning, it shows up on the scale. If it continues to go up, I know it's a red alert. I'm making the scale my friend.
MRC 8/23/13 - 10/31/13 - SW: 206.5, EW: 185.5. 21lbs down, 23.75" lost
My Weight Loss Blog