Abusive behavior is like, mmm, an addiction (?), people that recover are always prone to "go back|". It is like an alcoholic that has to conscientiously "choose not to drink" for the rest of their life. I hardly ever becomes "natural" not to drink, just like it hardly ever becomes "natural" not to abuse.
I'm not sure I'm ilustrating correctly what I am trying to say, I hope you get what I'm trying to say here.