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Has your daughter ever been tested for Attention Defecit Disorder? My 19 y/o did the same things (his dad walked out of his life as well) and I chalked it up to that. He did his homework, never...

My first thought when reading your question was J_9's answer. It sounds exactly like autism, and you and your friend cannot help that.
Autism Society of America:

I'm a mother of 3 grown children. I cannot for the life of me understand why "any" mother would treat her child in that manner. No it isn't normal. Narcissism is more like it.

Trust me, the heartache does mend in time. If the physical symptoms don't abate? Get yourself checked out k? You don't know who or what he was with.