A strong reaction can belong to the role you were placed in, rather than the event itself.

Roles come with scripts. Placed as the responsible one, the difficult one, the peacemaker, the disappointment, you find yourself reacting with an intensity that belongs to the position rather than to what just occurred. The feeling is genuine and its size was assigned before you walked in.

When a reaction seems larger than its cause, ask what part you were being cast in. Family gatherings are the obvious place, and workplaces do it too. Naming the role privately usually gives you a few inches of room you did not have.