My evangelical Christian family was very strict regarding religion, and I was raised to avoid anything secular, to set myself apart, and to see myself as not "of this world." I couldn't watch Disney movies, the Smurfs, The Land Before Time, David the Gnome, or anything else that could possibly be construed as the occult. All of my teachers were portrayed to be agents of Satan, trying to corrupt me with things like dinosaurs and Halloween. I was groomed to be unable to relate to people.
The extreme shyness began when I was homeschooled throughout most of elementary and middle school.
The SA took over when I went from homeschool to public school and had to relearn social skills in an environment that is less-than-friendly to the socially awkward.
I don't "blame" my parents because their intentions were good, but it's clear where some of my issues originated.