"Special Snowflake" is an insult. It means the person accused of it thinks too highly of themselves and that they feel the world should accommodate there every need and want. Older members might remember the expressions "full of himself" and "She thinks she is god's gift to earth" which has similar meaning.
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“Self Acceptance is a process not a performance”
“You are autistic enough. And you always have been”
Professionally Identified and joined WP August 26, 2013
DSM 5: Autism Spectrum Disorder, DSM IV: Aspergers Moderate Severity.