Dating

Why would someone contradict themselves after rejecting you?

Every good or flirty thing he ever said to me is now the opposite and supposed to be a sign of his obvious disinterest. Even stupid things such as how he stayed in my room for over an hour - the fact he stayed there for so long is apparently supposed to prove how uncomfortable he felt.
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Extra: I've recently been asked by his friend if I would take someone back who rejected me and who I think should make the first move in that situation. This friend has also told me that him and this guy were having a conversation about how stupid a guy would be to reject a girl.
Why would someone contradict themselves after rejecting you?
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