Full disclosure. I weigh over 300 pounds. However, I peaked at over 421. I hhave been riding since I hit 365.
I have lost over 100 pounds, and it was by doing the right things. Exercise and watching what I ate. I am somewhat stable at my current weight (and have been for way too long), and I am notching it up, for my health, and I want to ride an imperial century next year, and I want to lose at least 50 lbs to do it (I want to ultimately lose another 100+ and look forward to saying some day "I am half the man I used to be"😉.
I have tried various things to get me to the point where I am, especially Weight Watchers (effective for me, both motivationally and pragmatically for a year or so) I would urge you to give them a try, for at least long enough to learn their principles, in cas ethey work for you.
I have also studied, but not yet following a couple of plans to expedite my loss. I am currently reading the South Beach diet (which is not necesarily low carb except for the first phase), and another (even though I am male) I have read is the Curves plan.
I am probably going to attempt the South Beach diet....
But, the reason I started is that one of the elements in the Curves plan is that your body will adjust to your caloric intake, and they inject short periods of higher calorie intake, then back on plan to keep the weight loss going. I am not sure if this is effective, but it might fit in with your lifestyle.
South Beach emphasizes that it is not strictly about calories, but about how the body uses them, since foods with a high glycemic index increase the level of insulin and then after the blood sugars are processed, this leads to hunger. Foods with a lower glycemic index tend to keep insulin levels more moderate. Therefore, in the view of the author, the issue becomes eating the right combination of elements... some good fats (olive oil etc) and fiber mixed with the right carbs gives you all the nutrients you need, and does it in a way that avoids the insulin spikes.
My doctor a few years ago urged me to find whatever plan worked for me, and stick with it... Good advice.
Of course another plan is to simply spend more time on my bike, and less time at the table or on the couch. 🙂