I often asked myself, "How can they expect me to have been born knowing how to act?" I now suspect that normal people ARE born knowing in a broad sense how to act, or at least are born with the capacity to quickly form institutions for dealing with the world. People share a common humanity, and we--most of us--know by instinct, intuition, and common sense how to interact with others. Most people seem to say and do things automatically that I have to think through, sometimes successfully, sometimes not. I've been in groups of people of several nationalities and cultures, and they all knew how to make small talk and humorous comments--all except me. I was usually totally lost because I didn't have their sense of the right thing to say. I suspect that's the key feature of Asperger's--we weren't born knowing (or having the capacity to learn quickly) what to say and do. I think many Asperger's symptoms grow out of that frustration.
I'm intrigued that several people here mentioned leaving home early to get away from their parents. I didn't think that I had, but now I remember that in a way I did. In high school, all my fellow honor society members were going away to college but I wasn't--my parents didn't want to spend the money on me. But they wanted me to go to college (as did I)--it was what people in our circle did. So they were going to have me commute to college. But I had to get away from them, so I decided to join the army when I graduated without telling them. I mentioned this to a classmate, who told our guidance counselor. She called my mother in for a meeting. I don't know what she said, but my parents agreed I could go away to college. Typically, while most other parents were taking time off and driving their kids to college or at least to airports and train stations, I walked out of my home carrying my suitcases to a bus. At holiday times, almost all students couldn't leave soon enough for home, but I stayed in my dorm as long as I could to delay going back to my parents.
I've been wondering how bad my autism was as a child and if I overcame it (overcame by learning to act mostly normal, not cured it) because my parents wouldn't tolerate autistic behavior and forced me to act normally from the time I was in a playpen. I can't remember much from my first three years. Thinking you'll be killed, or at best kicked out of the house as my mother often threatened to do, is a strong incentive to mask.