E.J.
I am so sorry you are going through this.
This is a very difficult, resistant disease to treat. It is hard to find treatment centers for this.
Please,please have your entire family involved in the counseling: attend family nights, family therapy, and even individual appointments with the therapists if they recommend it. This is not just her disease. But carefully follow the recommendations of her therapists.
Treatment may take awhile, and may be expensive requiring family to spend days or weekends close to the facility.
There are frequent relapses. Learn to be supportive when this happens and see that the person needs more support at these times. Relapses are just small set backs and not a sign of failure.
Some people find support at OA (Over Eaters Anonymous). You can call and find out information about local meetings and family support.
I wish you luck, strength and peace.