Keep in mind that Dapsone can have some serious side effects, so be sure to look into those before you start using it. More about that is here: https://www.mayoclinic.org/drugs-supplements/dapsone-oral-route/description/drg-20063327

I suggest you look at your calorie intake. If you're not eating enough calories, your body will signal you to wake up and forage for more food. You need to be eating more calories than a healthy person of normal weight in order to gain weight. Also, your diet is extremely low in fat unless you are eating chicken thighs with the skin on, which I would recommend. Also be sure to add butter (real butter) to your vegetables. You can measure and record everything you eat, then look up and calculate what your protein/carb/fat intake is. Or just eat more chicken rather than filling up on vegetables and fruit.

Since your mother has celiac disease, I would still keep an eye on this as there is a genetic component. Study results vary wildly, but the numbers are that anywhere from 10% to almost 50% of the first degree relatives of those with active celiac disease will themselves develop celiac disease.

Your initial test showed a moderately raised level of IgA tTG2. There are several causes of this apart from coeliac disease including: inflammation of the joints, bowel and liver. Transient rise in levels can be caused by an infection.

Rogol72, your recommendation to the OP to "show them pictures of dermatitis herpetiformis" confuses me as the OP does not mention having dermatitis herpetiformis.