Thanks for choosing DoctorSpring for posting your query.
I have gone through your question in detail and I can understand what you are going through.
Obesity is considered stressful these days for the youngsters and it is quite apparent that your daughter is not comfortable with it and is certainly stressed out. If this stays for long she may even land up with depression which is not good.
She will certainly need psychotherapy preferably cognitive behavioural therapy. This therapy involves 20 min weekly sessions which focus on changing the way one thinks about oneself, others and the future. I understand that she is not willing for the same. Try convincing her with the best possible way and tell her that she needs counselling for loosing weight and not for her behaviour.
If she agrees well and fine, and if not the next best thing would be you can visit a therapist and he can guide you in the way you can handle this issue at home.
Hope I am able to answer your concerns. If you have any further query, I would be glad to help you.
Wish you good health,
Dr. Srikanth Reddy M.D.