Why Should I Write Down All My Anger and Hurt?

In this episode of Overcoming Betrayal and Addiction, Dr. Rob and Tami talk about the healing properties a journal practice can have. A listener wrote that her therapist wants her to journal out the resentment and anger that her SA has caused her, but the mere thought of doing this gets her re-triggered and angry all over again. Is there a point to journaling aside from re-remembering the betrayal?