Often when I evaluate clients' food journals, I find that they aren't losing weight because their nutrient intake exceeds their needs. I had one female client who was eating a large açaí bowl for breakfast that contained multiple servings of fruit, nut milk, nut butter, and seeds. She would then commute by car to work and sit at a desk all morning. While the bowl was chock-full of nutrition, it packed about three times what her body actually needed to keep her satiated until lunch.
Lots of people have, for their entire lives, used food as a reward. To restrict their own reward, and then not be allowed to have their reward after they succeed is tough. It’s like going into an apathetic void of brain fog and sadness. And sure, you can rewire your habits over time and eventually your body will self-regulate so hunger won’t be an issue anymore, but it takes time. This period is a trial by fire where many people fail.