You had a boyfriend, but he didn't really give you attention.

One day you went to his house and heard a girl talking and you heard kissing. You peeked and saw your boyfriend sitting on the couch, a girl straddling him and kissing his neck

You teared and ran out of the house, went to your own in the night, crying.

Next day you see your 'boyfriend' beaten up at school. And you saw your Enemy smirking