I've had this feeling ever since I entered into society, i.e. kindergarten. When I was a kid, I felt good in my family, since they really didn't pressure me into anything and they never seemed to think there was anything wrong with their smart child who fidgeted a lot, rocked, paced, spaced out in her dream world and her stories and was successively obsessed with cats, a few comics, dinosaurs and the battles (that went 2000 years ago) between the Romans and the ancestors of our nation... I guess they thought it was sweet and posh by then. They were accepting of me. And they never thought that my social isolation and failure to develop age-appropriate relationships with my peers was a problem (although I told them that troubled me a lot). However, now that I am a young adult and that they have NT expectations of me, I have disappointed them so much and I feel I don't really belong anymore to my family.
My point? As long as I was accepted and loved, I didn't feel as an alien. What actually make me feel like this is the rejection I get from people and the pressure towards conformity in society (and, as of late, in my family too). My NT friend who is gay can totally relate to this feeling, due to the isolation he encountered because of his sexual orientation. If society valued us and valued diversity, I bet we wouldn't feel as if from another planet...
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Probably 75% Aspie, 25% NT... and 100% ADHD
Aspie-quiz results:
Aspie score: 138 of 200 / NT score: 78 of 200 => Very likely an Aspie.