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"I often don't know how to read signals or to respond when I recognize them."
That immediately made me wonder if the LW might have nonverbal learning disorder. Having difficulty reading social cues, body language, and non-verbal communication in general is probably the most common symptom of NVLD. It's generally considered to be in the autism spectrum, occupying the place between Asperger's and normalcy.
http://en.wikipedia.org/wiki/Nonverbal_learning_disorder
Unfortunately there's no cure, but therapy can help the patient develop coping and compensation abilities. That might be something for the LW to look into; even if she doesn't have NVLD, there does seem to be some sort of issue there that should be addressed by a psychiatrist.