I have had a similar experience, and I’ve heard all of the medical nutritionist’s wisdom; First I must be eating too much, then it must be too little, then it must be sugar and junk food, then it must be lack of activity, then perhaps that I’m “too active” and causing my cortisol to be too high. I’ve been “correcting my gut biome” for decades now, too. When proven wrong with lab testing, journaling, fitness trackers, etc. I was accused of lying, and another time told it must be inflammation then, and a shrug of the shoulders with no advice as I wait for my next medical bill with nothing to show for it.
There are tomes of information from medical studies on genes and SNP’s, and conditions that impair - not caloric metabolism - but rather metabolism or breakdown of certain foods (and garbage additives and lab created vitamins/“enriched” items) that interfere with the body’s ability to utilize necessary nutrients which lead to deficiencies that impact body weight and body fat. Furthermore, chemotherapy and radiation have been shown to cause mutations to vulnerable enzymes that lead to the same. Still, they blame the patient more often than not and do not bother to look into any of the reasons behind deficiencies, or consider medical background. Then, when like me, you can no longer exercise 3-4 hours a day to lose weight even at only 20 calories over the Resting Metabolic Rate they lab tested you at, they blame your issues on what must be a lifetime of poor “lifestyle” choices (despite evidence to the contrary). Someday a new approach will be standard and people will not have to suffer like this. They will provide more individualized strategies, and scoff at the “old way” as they always do.

Do not give up! It is not your fault. It sounds as if you are doing the best you are able to do. Be proud of yourself for being so strong both physically and mentally/emotionally!

I understand that this won’t help you feel 100% better about yourself in a swimsuit or just out and about in this judgy, superficial society, but until the people tasked as experts change their minds and prejudices (and policies) to jive with the research, your best is all you or any of us can do.