Autism can often bring about social anxiety, because you're weird - and people don't get it. Not because autism automatically causes social anxiety, but because the social environment can make anxiety a pretty understandable adaptation.
This last point is important: autism doesn't automatically cause social anxiety. In fact, if you manage to get rid of it completely, you may turn into some kind of super hero that everyone wants to talk to.
Getting rid of social anxiety doesn't necessarily remove the underlying social mismatch, but traits which looked awkward under anxiety can become unusually compelling once the fear is gone. Directness becomes confidence, intense interests become enthusiasm, unconventional thinking becomes originality, and reduced concern for social convention can read as authenticity rather than awkwardness.
That said, exposure therapy can cut both ways. The more important lesson is to accept that you're weird, and realize that you only want to keep people who also accept that weirdness anyway. f**k the rest.
The goal is not to become socially normal; it is to stop being governed by fear of being abnormal.
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