A Wand With a Veela's Hair Core

After Voldemort is defeated, Bill is killed and Hermione gets bitten by Grayback. Fleur takes care of her, but after that, she leaves for France. Four years later their paths cross again, in Hogwarst. But why can't Hermione transform during the full moon? Why is Fleur acting like she was during the Tournament? And where in this mess fits the white wand with a Veela's hair core?