You are not alone! I've done that many times before! I would be doing great for about a week and then go bonkers. Almost like I "forgot" I was on a diet and eat everything in site. I can't even explain why it would happen. I do know I am an emotional eater.
This is what is helping me so far, maybe it can help you.
I've been doing spark for 3 weeks and it's helping me as long as I log on every day whether or not I think I've done well. The goal trackers are on my mind and I want to succeed.
I read articles, post and blogs everyday and look at success stories. It all inspires me.
The other thing is I'm trying not to focus on a "diet". I'm focusing on getting healthy. I just switched my ticker to count my fitness points instead of my weight. I DO want to lose weight, but I am focused more on my health. Sure I will be under/over my goals at times, but I'm not going to beat myself up over it! One step back does not compare to 50 steps forward...and forward is where I want to keep going!
We can all encourage each other. Remember you only fail if you give up.