protection spells would be a good idea, maybe a retraining order or something. i know it's hard especially since he's related to you, but try moving. while moving to a whole other city or state might be a step too far, maybe moving from one end of the city to the other might be a good option. [if you live in a city i mean]
if you're convinced a hex is the best, go for it, but i was pointing out Wiccan's would be against that no matter how much trouble you get into because you're causing harm. also, you might get some negative effects as a result of doing harm to another thanks to the three fold law. same if you don't do anything to him and decide to be positive [like moving or calling the cops] the three fold law most likely will reward you.