Willpower and diet: advice?

Since the beginning of September, I have been attempting a gluten-free diet. (I was tested and I’m not celiac, but eating wheat, and especially highly refined-flour foods like cookies, tends to make me bloated and give me diarrhea.) I also wanted to lose 5 to 10 pounds. I’m not overweight per se, but I possess a roll of belly fat that I (and my boyfriend!) would prefer to say goodbye too.

The first little while went well, and almost effortlessly. I was at the cottage with my family, exercising moderately (about 2 kilometers of swimming daily) and eating my mom’s excellent-tasting cooking. After about one and a half weeks, I had lost 5 pounds, although I suspect a lot of it was water retention/​bloating, since I had been eating wheat and various junk foods all summer.

Then school started, and with it my 16-hour days away from home, including one marathon session where I leave my parents’ house at 5:00 am on Monday morning, sleep at a friend’s house, and don’t come back again until 11 pm on Tuesday, only to work 5:30 am to 4 pm at the pool the next day.

In short: my diet is quickly deteriorating and I have regained those 5 pounds. I find it next to impossible to stay gluten-free, since I have to be incredibly organized and pack everything from home, and inevitably it isn’t quite enough for 16 hours. (I eat 3000 calories a day or more when not dieting. According to a metabolism study I participated in last year, this is actually how much I burn per day with the amount of exercise I get. If I eat much less, say less than 2000 for one day or less than 2,500 for several consecutive days, I get dizzy and weak when I exercise, which is really irritating.) I would probably be able to lose weight more easily if I exercised LESS, but this would a) kind of defeat the point, and b) be difficult because exercise is my main stress control method.

Willpower is a big issue, which is weird and annoying because usually it’s not a big issue for me. Especially when I’m sleep deprived (nearly all the time), stressed, or bored to tears in my classes, I tend to comfort or reward myself with food, and nearly all my ‘comfort foods’ have wheat in them. I can resist to a degree if I have access to other reward/​comforts, like sleep, or lots and lots of tea.

I’ve never really had to learn any willpower tricks for dieting, since I usually let my weight sit at its natural set-point. Does anyone have suggestions?