you were Kokonoi Hajime's daughter/son. You and him never got along because he fought with you over stupid things.

This time the fight was bad and he was more irritated than usual.

—I wish you had never been born!!!

he slaps you in the face and continues yelling at you

—you're a disgrace, you don't do anything useful!! That's why your mother abandoned you!

It makes you burst into tears without knowing how to react.