How "good" people go bad.
Exactly! It's not always the "inhuman bastard" that becomes an abuser, it's the people who are convinced that they are good and have the RIGHT to do "disagreeable" things in order to create and maintain an "empire" of "goodness" that is "satisfactory" (even though it is only really satisfactory to THEM).
Very often, it is the seemingly harmless and self-proclaimed "alpha male" jock or the "man of the household" (sexist and condescending attitudes are taught by society) that were taught to be the "controller" of a relationship and doesn't have the insight to understand that a relationship should be SHARED, not controlled, and CAN (they have the ABILITY) present themselves as a nice person (they have an easy time being deceptive to most people, but ESPECIALLY to those closest to them).
The abusers find that the easiest people for them to control are the most loving and tender hearted, the most trusting and the most decent (noble), not only because they are the perfect prey, but because the tendency of the noble is to be "redeeming" of others and will also avoid returning conflict (for the sake of peace).
The abusers will avoid rational discussion and thought (lest their victim see the truth of the situation) and will fear and resent any possible intrusion into their empire (controlled environment, their chosen reality, their empire is fragile and must remain intact, it cannot withstand challenge from rationality/OBJECTIVE truth).
It is extremely naive to think that they can change (short of a drastic life-changing event). There are abusers who enjoy the control and ego boost of INTENTIONALLY "causing evil" (who will also enjoy CAUSING imperialistic happiness, "Wasn't it nice of me to stop ----?...that's because I am a good person), and the well meaning who don't know any better but simply don't have the ability to RESPECT (they can APPEAR innocent).
The ones who demoralize their victims in public are not only also doing the same at home, but have found their perfect prey (and will be possessive of it) and may even be undetectable as predators to friends (cry terror, for demoralization is only done to ENEMIES and prisoners).
Mischevious youth can become monsters if we let ourselves be convenient to them and redeem them by being apologetic, but the abusers who intentionally cause evil and the ones who demoralize their prisoners will most likely be DANGEROUS because they are "hardcore" abusers.
It is the noble heart and mind of the victim that is most attractive to the abuser because it offers stability in the abuser's life of chaos and confusion, and it is the abuser's realization that the abuser cannot match that nobility, that is what causes the resentment of the victim (in other words, the abuser has not built the relationship on love, the abuser has built it on resentment and will "possess" the glory of nobility, mock, control, and USE it also).
"Good" people go bad by having a NEED to CALL themselves good, so, really, how good can they be in the first place?