Your daughter is fortunate indeed to have such a concerned mom. I can’t tell you what’s wrong on the basis of a letter. Although different professionals have come up with different labels, it seems they do agree that something is amiss.
But, truly, I’m not sure it matters what the diagnosis may be. Your daughter is troubled and troublesome. I suggest you stop looking for a mental health diagnosis and take a more holistic approach. First, if you haven’t already, take her to her doctor for a complete physical exam. That should include blood tests to make sure there isn’t a thyroid problem that is contributing to her difficulties. If so, start treatment. If everything checks out medically, then have her evaluated for a learning disability. Sometimes kids with learning differences miss important social and emotional cues and this causes erratic behavior.
While you pursue appointments, make sure you are taking care of the basics. That means encouraging her to get enough sleep and good nutrition. Finally, seek out a therapist. At 15, she is old enough to benefit from some individual therapy, regardless of what is at the root of her problems. I encourage you to find a therapist who works with teens and their families. The whole family has undoubtedly been affected by your daughter’s behavior. Good therapy will include regular whole-family sessions as well as individual treatment for her.
I hope that taking a slightly different path will help your daughter get unstuck. I’m sure the last few years have been terribly frustrating to you both.
I wish you well.