This is a fairly common stock motivation, in which a character who has been abused, persecuted, or otherwise mistreated in the past is acting to make sure that this sort of thing never happens to them again. This can encompass anything from taking a few levels in badass to ensure they'd be able to defend themselves against future threats, to attempting to Take Over the World and overthrow the oppressive institutions that made them miserable. The character may also wish to spare others from suffering like they did, but there needs to be at least some element of preemptive self-protection involved to fit the trope. It's a common motivation for the behavior of the Broken Bird. See also Freudian Excuse and My Greatest Failure. If the hurt is romantic in nature and new relationships are avoided