As a recovering anorexic, I recognize your post. I recognize it because it seems like many of the posts I've read and written myself in ED forums. I feel that if this really did happen, and your doctor really did put you on a 500 calorie diet, then you need to see a new doctor and abandon this diet. Even for the morbidly obese, 500 calories is insane. If this didn't really happen (sorry if my words offend) then I'm here if you ever want to talk, and I suggest you notify someone in your family of your condition. The only reason I assume you may have an eating disorder is because you included the phrase "triggering" at the end of your title, and the only other place I've seen that used is in threads that may trigger a person recovering from an ED back into their habits. PM me if you want to talk at all. If I've misjudged the situation then I'm very sorry.
EDIT-I understand that the phrase triggering was added by a mod, but I stand by my offer if you do have an ED and would like to talk, again, if this was not the case I'm sorry.