There are experiences in life that drastically change us forever. We are of course a product of all our experiences but some things truly have a life altering effect.
As the years go by we learn to "live with" these memories. Only the most naive expect us to "get over it." We don't. We carry the wound inside forever. Periodically something happens that brings that experience to the forefront of the brain. It threatens to absorb our thoughts, the scab is, effectively, ripped off and the wound bleeds again. Having your tormentor defended in any situation is unconscionable to us. When ones children are involved the rage is comprehended only by another mother. I am getting to old for all this drama. I should adopt the ancient Jewish custom of burying a box of stones and declaring the person dead. Maybe then I would gain some peace.