those two flaws , combined with a desperate yearning to make her father love her , as he loved his stepsons , were responsible for the debacle she 'd made of her life : when she was fifteen , those were the things that had led her to try to avenge herself against her sly , spiteful stepbrother in what had seemed a right and honorable way-which was to secretly don merrick armor and then ride against him , fairly , in the lists .