One month after the accident
It wasn't jealousy that turned Sam's general disdain for Paulina into a very specific loathing after their first high school dance. She and Danny were just friends, after all (never mind that spark of… something she'd felt during their one dance together.) And while she'd been annoyed that he would crush on someone so… cookie-cutter, if Paulina made him happy, Sam was willing to make an effort.
It was only when she found out Paulina was using him that she really lost it. The shallowness and the narcissism she could get past. But hurting Danny? That she could never forgive.