I've done this too, many times! I try to learn from each time I go off track, but the more important thing is to get back ON track and not to beat myself up over whatever it was that I allowed to get me off track.
Sometimes getting off track means that there is something about my "track" I need to change. Maybe I'm bored with my exercise and need to step it up, or maybe I'm bored with my food and need to find a new recipe. Or I'm stressed and need to pay attention to that. Whatever it is, I can't change the past, so I try to just focus on what I can do today to get closer to my goals.
My Sparkpage is set to private, but I'm open to SparkMail!
"People often say that motivation doesn't last. Well, neither does bathing--that's why we recommend it daily." - Zig Ziglar