Noun
trauma - A deeply distressing or disturbing experience, especially one with lasting emotional impact; a psychological or emotional wound, often resulting from an intense or life-threatening event.

Childhood trauma can have long-lasting effects on a person’s mental health
vendetta - A blood feud in which the family of a murdered person seeks vengeance on the murderer or the murderer's family

As the final act of his vendetta against Rugen, Inigo pulled out his sword and said, "Hello. My name is Inigo Montoya. You killed my father. Prepare to die."