Of course it didn't last. And of course, of damn course, she was the one who broke it.
They dated for a whole year. Twelve months and four days, but by then the slow corrosion of her failures and Melanie's restlessness had already degraded their relationship to tatters, to the point where they were just waiting for the end. They weren't friends anymore, not even close. Rolanda had fallen in with Slytherin girls, absorbing herself into their recklessness, their giggling bad ways. All Melanie talked of was studies- 'OWLs this' and 'OWLs that'. They had nothing in common by the end, but still, they kept it going.
Because they were Hufflepuffs, and Hufflepuffs don't give up, even when they should. They value patience so they put up with hell, they care about loyalty so they blind themselves to each other's faults. Still closeted, still young, Rolanda had thought herself so unique. So bloody helpless.
She hadn't meant to snap, though she was glad of it, she was glad when it was over. She hadn't meant to say mudblood, she hadn't meant to say frigid.
But she did, she said those things. And no amount of time can heal such shame.