How did victor lost his humanity at the end of Frankenstein?

At the end of "Frankenstein," Victor Frankenstein loses his humanity as he becomes consumed by revenge and obsession in his pursuit of the creature he created. His relentless quest to destroy the being leads him to sacrifice his relationships, health, and ultimately his life. This transformation highlights his descent into isolation and despair, stripping away his compassion and moral integrity. Ultimately, Victor's inability to take responsibility for his actions results in a profound loss of his humanity.