A guy I rejected once rejected me later when I approached him. I moved on. He fell for me again and wanted me back. I fell for him back. He left. Why?

He is acting hot and cold. What should I do? Leave him and find someone new? Or beg him to make him stay?

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8 mo
He's my first love and I'm his first. That was the only reason due to which I stayed with him despite the disrespect that he did to me
A guy I rejected once rejected me later when I approached him. I moved on. He fell for me again and wanted me back. I fell for him back. He left. Why?
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