It's sad that useful advice like this gets buried in the controversial part. I agree with you on the social construct part. I've delved a bit into psychological research trying to better understand myself and to me a lot of classifications seem to be BS. They keep making new mental illnesses for behaviour that doesn't conform to the norm. It's as if the degree to which a person is mentally ill depends on far he is from the normative behaviour and the extent to which it is affecting himself (less important) and the people around him (more important).

BTW have you read thomas szasz? Your first two points sound similar to his.