Question for OTHER GUYS: how did she switch up on you?

I think we've all been there before, you liked a girl and she seemed to really be into you as well, and then suddenly she changed up on you. What is your experience/experiences? One of mine was once a girl who was falling all over herself for me and other people said they noticed it too, and then later she started acting mild and every time she talked to me it sounded more like one of your co-worker trying to be professional or something lol. Then of course I found out she was sleeping with someone and that explained the switch-up.

So what are you guys' stories?

Question for OTHER GUYS: how did she switch up on you?
Question for OTHER GUYS: how did she switch up on you?
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