Fourth year he ignored her femininity, part of which was Dumbledore's fault. Then he got mad because she wasn't just sitting around waiting for him to need a date. His resentment boiled over that night, he insulted her date, her appearance, and ruined the end of the night for her, forever tainting those memories. And that was after he abandoned Harry! She knew the charms had fueled her emotions then, and the emotions related to them weren't quite her own. And even when he came back he never apologized. Third year after the broom incident he made her grovel. He treated her like the dirt beneath his shoes. And it wasn't even his broom.