Question: Maddie is brought to treatment at the recommendation of her physician. Over the last six months, she has gone from a healthy 125 lbs. to a concerning 98 lbs. She lost weight by significantly restricting her caloric intake. She reports that she just wants to lose a few more pounds to reach her goal weight, so that she no longer feels fat. When told that she is far below her ideal weight, and that she should be on a meal plan that supports weight gain, she became extremely anxious and tearful and accused her physician of trying to make her fat and ugly. Maddie is most likely experiencing what diagnosis?