blindsided

i don't usually feel homesick when i'm away from Singapore. In fact, if i'm not mistaken, i've never actually felt homesick for Singapore before. i might vehemently dislike the place i'm in, but i've never actually missed Singapore. At most, i miss the food. But even then, i just never get it as bad as some other people seem to.
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But today, watching a film about an autistic high-school math geek set in England and Taipei, i think i was blindsided by nostalgia. What exactly is it that i miss? City life in Asia, i guess, and teaching young math-and-science geeks. And the England of my memory, from my undergrad days. But that was a long, long time ago.
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