You say you're the thinnest and fittest you have been as an adult. That's no small accomplishment! So, what's wrong with just 'keep doing what you're doing'?
If you're obsessing over crap food, then that has to do with your diet program/ beliefs. I finally have cycled through all the diets - there have been many, and all successful for the short-term - and now I've discarded the whole idea of 'bad foods.' Some diets push that idea, 'bad foods,' more than others. I recently had some fast food and, believe me, it was very affordable on my (Weight Watchers) diet. I had been craving a Big Mac, or something equally jumbo, fatty, salty and tasty. I challenged myself to stick to a Happy Meal. It turns out that the new, more 'healthy' Happy Meal has a tiny portion of fries and some sliced, fresh apples. I didn't even know that! It's fewer calories, but still a splurge. After I ate that for lunch, it was much easier to say, 'I don't need that Big Mac.'
The point is: your diet isn't made up of fast food or pastries or cakes. Even if it was, you'd still lose weight if you ate fewer calories than you burn. Sodium jacks up your weight and that's a drawback to eating a lot of fast food. But - come on - calories are on the McDonald's box. You add 'em up, you stay within the limit you've set and THAT's where your success lies. Obsessing that a food is bad and off-limits is going to make that food always sing its siren song for you, while other foods seems angelic in comparison. As my WW leader often says, 'You can get fat eating too many bananas... but people don't eat too many bananas, they eat too many calories, which are packed in densely delicious foods!'