aml, I wish I had some good advice but I'm afraid I don't.
But I can relate! I've been totally off the wagon for about 3-4 weeks now. I can't bring myself to log onto my calorie counter, I eat 2-3 bars or cookies a day instead of like half of one when I'm OP. I exercise like every 2-3 days instead of an hour everyday. I haven't really gained weight but I have gained inches and my previously loosening clothing is feeling oh-so-snug again.

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I've always found it helps to go read the goal and mini-goal sections. Also, go to the NBC Biggest Loser page and look at the submitted photos of viewers who've been successful at weight loss.
My biggest motivator right now is I am 1.5 lbs away from getting out of the obese BMI category. The past two days there's been THREE people who've posted that they are no longer obese and I'm so jealous! I'm so close, yet that's 5,250 calories I need to avoid/burn. I also thought it would be the most wonderful thing to say 2008 was the last time I was obese, so I've got less than a week.
Also, there's some Biggest Loser Challenges starting, the 20-something one and the main Biggest Loser Challenge, that's in the Exercise forum. I'm doing the second one and again, I want to start it out at 158 lbs. Those challenges helped me a lot, I never wanted to let the other people on my team down by eating too much/not exercising and consequently gaining.
My motivation is back like... 50%. I feel like I'm just going through the motions but hey.. I'm doing something!
Sorry I can't help you more.