Family scandal: She made a habit of visiting the folks on the "wrong side of the tracks" for months now, because she found them to be pleasant, kindly people free of her family's pretentious aspirations. Oh, and when we say "wrong side of the tracks," we mean literally because they live across a railroad tracks.
Anyway. The scandal worsens because the girl regularly got drunk with her new friends, and would always collapse/fall asleep on her way home. Right on the railroad tracks. But by a miracle, her catnaps always ended with a generous margin of time before the train came rollin' along. Also, perhaps, the protagonist could always pick her up an hour before dawn from the tracks, like clockwork.
Then, one night, the train conductors changed the damn schedule.