Lencho3 is right it not about the food as much as with you thinking the rest of your life is out of control but you can control how much you eat.
a dietitian can only tell you what you need to be eating, they cannot make you eat. you also need a therapist, preferably one that has dealt with anorexic patients.. they will also be able to determine if some kind of medication would be helpful to you.. but if your weight is dangerously low, hospitalization might be the best option. there are in-patient clinics that deal with eating disorders...
a dietitician is just a life coach it is up to u to make the necessary changes all she can do is support and guide u
the problem is in your head you need to think what got you to stop eating that the thought you have to fight
But, is it thyroid related or is it because you don't follow your diet?
Then you need to go to a doctor and take medicines for a hypothyroidism. Don't go to a dietitian. You don't need one if your eating habits are fine.
A Nutritionist, notta Dietitian