Dillon pretty clearly demonstrated in the movie that he was not only no longer a rapist, he actually saved her from being gang raped by men that he considered his brothers.
After that he demonstrated that he was no longer a murderer when he couldn't bring himself to kill her, despite his earlier assurance that he was up to it. Hell, he wouldn't even let her die in the mold.
In short, if you take away his "murderer and rapist of women" line, you grossly undermine the impact of what he does later in the film.