I think there have been studies showing that, most men and women can tell when a man is interested romantically/sexually in a girl from when he's just being civil to her from when he wants just friendship - however, when watching a woman, both men and women usually cannot reliably tell whether she's interested in the guy or not. And guys misinterpret signals, in mistaking flirting for friendly interest as well as friendky interest for flirting, most of the time. These were studies with the overall population, not just aspies.
I personally can't tell the difference, much worse in my view, cannot tell the difference, at all, between fake flirting (flirting for the sake of flirting without any actual interest) and real flirting (when she's actually interested - I'm not saying marriage, but as in talking to me again or getting to know me better). Fake flirting I view as a particularly selfish mind game and I find it contemptible.
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I am the steppenwolf that never learned to dance. (Sedaka)
El hombre es una bestia famélica, envidiosa e insaciable. (Francisco Tario)
I'm male by the way (yes, I know my avatar is misleading).