The objective was to find all the root causes of the problems you saw in your daughter, and it sounds like through a wonderful partner in Joel and a very good neurologist you have. Kudos to them, and to you for stepping back from your anger, and forgiving Joel. I had a somewhat similar experience, yet different and unresolved--at the time--outcome.

The teachers at school were concerned because my youngest son was so quiet, and recommended family counseling. (Side note: Susan Caine's book Quiet is a marvelous discussion on why we as a society have gone from seeing quiet as a strength as in the strong, silent type and now see it as a problem in a world of hyper extroverts.)

The four of us -- my wife, and two sons -- went to family counseling. At the end, the psychologist -- who had been observing all of us -- said the problem wasn't our youngest son, but the older one. That the younger son observed what his 7 years older brother did, saw what trouble it got him into, and rightly chose to avoid that kind of behavior. Psychologist recommended ongoing family counseling with the older son, not the younger.

Oldest son was a teen; absolutely refused to go or accept any responsibility for his actions. Took years and some traumatic experiences for him to turn his life around, and rebuild bridges with the entire family. Point being, you are at least thinking and considering your role in the problems your daughter is exhibiting. Kudos to you.