How does the monster in Frankenstein changing his attitude fit with the theme of duality in the novel?

At the end of the book, Robert Walton encounters the monster, after Victor dies. Maybe the monster feels bad for Victor? Because then the monster wants to destroy himself and then goes to the north. How does the monster鈥檚 behavior and attitude affect the way you view him? Because in my opinion, the monster feels bad for what happened with Victor and hates the fact that he will never be human or is he hateful because he relents only after his creator dies? How does the monster changing his attitude fit with the theme of duality in the novel?How does the monster in Frankenstein changing his attitude fit with the theme of duality in the novel?He's part Human