Geez...flirting... I empathize with all those on this thread who feel baffled by it, and thank you all for sharing! I may do pretty well in some areas, but this one is a serious Achilles heel for me. I am extremely grateful that I found true love and got married without having to engage in society's mating rituals! We ended up doing an old-fashioned courting without either of us even realizing it.
I never understood this one at all when I was younger, and it's still just a weird intellectual exercise for me. I got really lonely after high school, so I did a ton of online research on improving social skills and tried to figure out what this "flirting" thing was they talked so much about. I don't think I ever feel more "Aspie" than when I read stuff about dating, and what's actually involved in flirting and the kind of social stuff that NTs do.
It bugs when I can tell that someone is trying to make me react in a certain way. I hate feeling like I'm being manipulated, even if it's a "nice" manipulation. But I love it when flirting-type behavior just emerges naturally because you meet someone you click with, and you naturally feel good being with them.
I didn't know I was an Aspie until recently, so before that, I chalked up my lack of sociability to growing up in an insulated Christian household where any kind of mention of sex or even dating was taboo. So not only was I an Aspie, which makes it difficult for me to do most social things, but I also had an environment where dating simply wasn't done. The only friends I had were guys who were into the same things I was, and I had no idea how to interact with girls. I didn't even realize that people went to bars to do anything but drink and play darts!
What's worse--apparently, I'm good-looking. I say "apparently" because eventually, enough external evidence piled up that I had to warm up to that conclusion. But it's not part of my self-concept or self-image at all. I'm pretty sure that when you're good-looking, the last thing people expect is that you have limited social skills. So I've had a ton of encounters with women of all ages who want to interact with me, and I've doled out an awful lot of rejection, sometimes without realizing it, the rest of the time, because I have little desire to interact with strangers. I'm amazed at how many super-pretty girls consider me in their league.
Being married is great, because now I'm supposed to ignore other women, but there's still that brand of flirting women do that's done for fun and not with intent. I can't tell the difference at all, and I don't have much ability to respond to it, regardless of intent. It's weird to me that people want to befriend someone just because they look pretty.