Keeps score and holds grudges
Three years later they still mention the bonus that went to someone else, or the comment you made at a dinner.
Rule out first
A real unfairness that was never addressed. A culture where favours are tracked. Grief that hasn't been processed.
What could explain it
Organisational justice: The grievance is specific, others saw it too, and it would settle with acknowledgement or a remedy.
Resentment: They replay it privately and grow more bitter, but have never told the person directly.
Punitiveness schema: They're as hard on their own mistakes as on yours; forgiveness strikes them as weak or unfair.
Paranoid personality: Many of the slights were neutral acts read as hostile, and the list keeps growing.
Psychological entitlement: The grudge rests on what they felt owed, not on anything anyone promised.
Mutual recognition (Hegel, Honneth): The grudge is about not being acknowledged, not the loss: compensation didn't end it, and the story keeps coming back to 'nobody even said'. A specific acknowledgement in person shifts it.
A next move
Ask what would settle it. A concrete answer points to a real grievance. 'Nothing' points to resentment, punitiveness or paranoia.
If it’s you
What would it cost me to let this go?