Do women just not catch feelings or get attached after sex anymore?

I spent all Halloween weekend with this woman. We spent all weekend in an AirBnB with my friends and their girlfriends and on Sunday night, she became distant and left without waiting for us saying that she had things to get done before Monday morning. Ever since, she has been polite and friendly, but there has been a shift. I’ve asked her multiple times, what’s wrong and what did I do and she keeps saying nothing.

My friends with benefits before this, he only contacted me when it was convenient for her and she dumped me, then got a boyfriend the next day.
Do women just not catch feelings or get attached after sex anymore?
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