Hi Anonymous - Thanks for sharing your story and bringing your concerns to EmpowHER.
First, a comment about your doctor. As scientists, doctors tend to see things in black and white, relying on evidence based data to form opinions. It's not surprising that your doctor would say that a negative test for celiac disease would mean that you do not have celiac disease, which is a digestive and autoimmune disorder.
That doesn't mean that your own testing through an elimination diet was inaccurate and should be discounted. You know your own body better than anyone else, and your detective work is something to be applauded as not many people would take the time and effort to do this.
There is increasing evidence that gluten can promote inflammation in the body even when a person doesn't have a specific allergy or sensitivity to it. I suggest you continue your detective work, but instead of focusing only on gluten that you look at foods which trigger inflammation and inflammatory reactions. The goal, after all, is to feel better and to be able to eat foods that don't interfere with your health and well-being.
I am sorry to hear that you are also dealing with thyroid cancer, and hope you are getting the help and support you need. An anti-inflammatory diet is often recommended for cancer patients/survivors, so that's another reason for you to continue your anti-gluten diet and to research anti-inflammatory diets too.
It really doesn't matter what other people think about what you do, and don't do, with your diet. What's important is that you trust your gut, go where your own testing is leading you, and adopt the diet that is best for your health and helps you feel good.
Hope that helps and you will keep us informed of your progress.