Identify a theme in the Count of Monte Cristo and explain it (29)

One major theme in The Count of Monte Cristo is that of vengeance, which becomes Edmond Dante's reason for living. Dantes is consumed with the idea of revenge, revenge against Fernand Morcerf, Danglars, and Villefort. Every year that Dantes spends in prison only serves to strengthen his resolve. He knows he is the victim of injustice, and as a result, he wishes to have his enemies suffer also. During his imprisonment, Dantes resolves to take all the things they love and consumes his time orchestrating their downfall. Dante's desire for vengeance consumes him. He is blind to everything but accomplishing his goal. He cannot see Haydee's love for him, and he cannot enjoy his life. By the end of the novel, Dantes realizes that his quest for vengeance has, in fact, corrupted him in the same way as the men he seeks revenge against. Thus, he decides to leave with Haydee and build a better life.