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There is definitely something wrong with her, although with her constellation of symptoms, it could be a few different things. Let me give you a couple links to see if any of them fit, which can then at least start you off in a direction for help.Schizotypal
... This one takes into account her isolation, fantasy world, odd speech and lack of formation of realistic goals.
Compulsive OvereatingComputer game addiction
(in you daughter's case, writing the fantasy book is similar to an alcoholic becoming a bar tender...it's a way to legitimize and rationalize the problem, making it seem to be a 'solution'.)
Underneath any of those, she is probably depressed or has anxiety
. I recommend that you read those articles and see if any of them fit, and then speak with your doctor about the path they recommend for evaluation and treatment.
My best to you.
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