Your daughter needs a complete mental health evaluation to find the correct diagnosis. It is possible she has some chemical imbalance which causes her behavior and if she can be helped with medication, it is no different than a diabetic who needs insulin. Many parents feel as you do and resist medical intervention or believe that if they are good enough parents they won't need it. The truth is mental illness is very common and some of the most productive members of society have been plagued by this.
Fortunately we now have excellent medications that can help most disorders so that people can lead productive and happy lives, free of the problems that have interfered at times. Be patient because it can take a while to find the right medication or combination of meds and/or therapy. It is worth it!
There are many types of problems but a good doctor and therapist can help you find answers. You might try a mental health clinic, perhaps through your local community health arena. Another good resource is NAMI (http://nami.org
The answers in online forums are for information only and are not intended to substitute for medical advice and care. Please see your personal health care provider for further evaluation of your individual case.
Debbie Miller, RN