Hello, Sesheta
Much sympathy. I'm struggling with the same problem. When I expressed frustration to my doctor, and commented that I knew that I wasn't eating more, he remarked that it might be because my GI tract was healthier now and absorbing more of what I ate...that made some sense to me.
I'm also in the metabolism slowdown that comes at midlife. It took me awhile to understand that not only could my GI tract be absorbing more of the calories of the food that I ate, that my baseline caloric limit had moved lower. It's one of my life jokes that it all happened in about the same period of time, thank you very much
In other words, celiac or no celiac, I now was maintaining on fewer calories than I had been maintaining in my early adulthood. And my GI was back to its business taking in those calories from what I ate.
A third factor is that my life definitely has become more sedentary in the last 10 years, especially the last 5. There's another overlap. This in my case is partly due to the computer. Work outside the home takes up most of my day, and it has shifted over to being done on the computer. I no longer move around, inside and outside my work building. So especially at work, I'm burning fewer calories per day...and those little puppies mount up. I suggest that you check this out in your life, too. You may not be nailed to the computer like I am these days, but how sedentary have you been during the period in which you picked up that extra weight?
From past years when I was jogging regularly and running in road races, I can tell you that at least in the case of my body, maybe not others', I have to do what for me is a massive amount of aerobic exercise before exercise takes off any weight at all. For me, I had to get my miles run per week up above 35 (56 kilometers), habitually. I can run off 200 calories or so in the gym but I don't get to the gym every day, so it would take me over a month to exercise off that 3500 calories = lb. off. That's much too slow for what you and I want concerning weight loss.
So for me, weight loss comes down to a matter of number of calories in. Perhaps other members can suggest particular diets or emphases in diets (carbs, no carbs, what to do about dietary fat)
I think people may differ in what psychological strategy works best for them, so I don't urge these following on you But they're necessary to me.
1) I count calories. I really have done everything I can to avoid this...it feels so compulsive to do it But if I don't count, I don't end up making aware choices in the "danger times" of the day.
1a) I sometimes think different people have different needs for the ratio of meat to veggies, but I'm definitely someone who does better on lots of veggies, very little meat, and low on the carbs, so that's what's best for me as I try to lose weight: lots of veggies. I even do well skipping meat protein entirely some days of the week, doing it on things like lentils or hummus: legume protein. I do think you'll need to maintain a ratio of meat to veggies that your body needs, or you'll get some hunger drives related to your body feeling depleted of something that it baseline needs.
2) I shouldn't eat after dinner in the evening, period. I'm working on this one. When I was worst off before I learned that I had celiac sprue, I was ravenous, because my GI tract was not absorbing nutrients. There's no opportunity to eat at work, so my time to eat was in the evening..so I became habituated to opening that refrigerator door in the evening. It just packs on, and if I ate carbs in the evening, oh boy. See 3)
3) Drink water, lots of it, and keep exercising. Because of my age, genetic history (my father was a diabetic) and sedentary work, I tend to stack on water weight. This is very demoralizing. If I haven't had some good exercise, haven't been drinking water, and eat some carbs, I can pick up 2-4 (1-2 kilo) of water weight in one day or evening, and keep it on. I can carry so much that my clothes actually fit differently (so I am constantly reminded and feeling fat all day). For me, I need to do exercise that gets my legs moving: walking, treadmill, working on the elliptical trainer. Once years ago I took a diuretic pill..what a dreadful thing it was..it wasn't a silver bullet, and the caffeine in it kept me stuck to the ceiling for 2 days. Drinking water and doing exercise that gets me moving takes care of the extra water for me.
4) It's not weight loss, but a contribution to your beautiful moments on your wedding day might be to work on muscle tone. That's where calisthenics and working on the weight machines help.
5) People will vary on this one: I need to weigh every day. If seeing the measured weight stay the same although you know you've tried that day, or see a couple of extra pounds of water weight push the needle up upsets you, you may not want to weigh daily, but I'm in the middle of changing how much I eat, really changing some baseline habit on that, so need to be aware, just now, and so I need to get on the scale often.
6) I need to take a multivitamin.
Once again, these are things I have to do, daily, to make a dent in weight loss. They're not direct recommendations to you, but I hope some of them have enough match to your life that they might be worth trying.
The one thing that I think I can report, regardless of your age or how sedentary your day is, is not to expect that exercise will take much weight off, on the timetable that you'd like. It's good for health, muscle tone and feeling good...part of an overall lifestyle.
Congratulations on your upcoming marriage

You will be beautiful on your wedding day and you're be-yoo-tiful now. Stay in touch!
Your fellow dieter