Hey girl, I'm almost 2 years post op, but I had already fallen off the band wagon... I'm just glad I realized sooner rather than later. About a year ago, I had popped down to my goal of being 160lbs and even popped below that a couple lbs every now and then, but slowly got out of going to the gym and letting old habits seep back into my life. I finally weighed myself and saw that I had let myself get back up to 174. I have been telling myself that bouncing around 155-165ish would be fine as long as I knew my measurements were staying ok, but when I measured myself, I had gained a number of inches (including 2.5 inches in my waist and almost 3 in my hips!)
There are so many out there who fall off as well. While I haven't discovered a 'trick' to getting back in the swing of things, I have found a few things that help me out. I'm just getting started back on track and already down to 167.4.
I had RNY, so it may be a little different getting back to your healthy lifestyle.

Whenever I found myself craving more carbs and having a hard time saying no, I found that forcing myself to do an all liquid diet (full of greek yogurt(blended with sugar free popsicles), chicken broth, and a ton of jello) for a few days really helped me to feel the restriction of my pouch again. I guess I did a sort of modified 5 day pouch test since they usually say to slowly add in solids, but I tend to stick mostly to liquids the entire 4-5 days.

I like to go shopping with a friend when possible. My best friend eats super healthy, but even on the off-day she might buy a quart of ice cream or something, it's helpful to have her around since she knows I'm trying to stay on track and where I was before. While I know she doesn't judge me, I just feel ashamed to buy junk food when someone is looking over my shoulder at my purchases.

I also really like playing with my food to find new recipes. It's crazy to think of all the high calorie choices restaurants make when preparing your food. You can usually make the same meal at home with a lot fewer calories and fats. I used to LOVE going to the Flying Biscuit and having their blackened tilapia tacos smothered with sour cream and salsa and cheese and all that.
Now I make a much healthier version at home using lo carb tortillas (80 calories for the whole thing), greek yogurt in place of sour cream (I honestly can't tell a difference now), a little salsa verde (10 calories), whatever lower fat/calorie cheese I have around, mushrooms, and grape tomatoes. It's one of my FAVORITE meals now and a whole taco generally lasts me for 2 meals, especially since I like to have a small fruit or veggie with it.

If you ever feel like you are missing a somewhat asian feeling dish (nonfried of course though), I like to make shrimp stir fry. I just get a cheap bag of stir fry veggies from walmart and cook them up with garlic, fresh mushrooms, onions, and any extra veggies I have laying around (usually zucchini or something). Cook up the shrimp and toss them in with the veggies and some stir fry sauce. (The sauce is not super healthy at 40 calories for 2 tablespoons, so I try to focus more on making it taste garlicy), but with the low calorie-ness of the rest of the dish, it really isn't a big deal to add a little extra sauce from time to time.

I also make tortilla pizzas a la eggface pretty often.

When I first started the consult and education part of my journey before I was even approved for my RNY surgery, one thing was pounded into my head from the staff at the surgical center. WLS is NOT a quick fix. It is simply a tool that forces/allows you to change your lifestyle. They told me that 50% of weight loss surgery patients gain it all back within 5 years. Even with the RNY it's possible to become accustom to eating sugar/carbs again and gain it all back. For those us that are big, and always have been big, this will a battle we will wage for the rest of our lives. We always have to be vigilant. Many of have issues with food addiction and we must work on our "head problems" as well as our physical issues. The surgery only helps with the physical part.

I never hit my official goal weight, however I've gotten down to a weight where I'm happy. I mean, who wouldn't be happy with losing as much weight as a whole person?! Anyway, I stalled there, and I was okay with it. I was still going to the gym regularly, however I started to let old habits fall back in over the period of a few months. I picked up 5 lbs between 10/13 and 12/13 last year. So, I started tracking again, and quickly dropped the 5, plus another 5 more. The important part is that you keep vigilant and notice when you start picking up weight or inches. I personally don't think fluctuating over the same 5 lbs is all that bad, however when you see a continual gain for a few months, then it's time to get back to business. Really, I think this is just part of maintenance.

What I have learned 15 months out is I need to keep going back to my surgeon even if it's just for a pep talk. I was so upset in Dec when I hadn't lost anything since May when I lost my initial 40lbs. He gave me a fill but also reminded me of the rules and told me that just owning up to the fact I was slipping and making the appt. to come in for an adjustment was a huge step. I have been going back every 4 weeks since, no fills but I am close to the green zone and almost another 10lbs gone. He gave me a great pep talk last week that has really given me new motivation.