We humans often are stopped from being allowed that natural completion. We are medicated, or told to not cry, told it was no big deal, or even that it didn’t really happen, or to suck it up, be a man, be strong, whatever. And so the trauma experience has nowhere to go except deep inside the body / mind. The internal containers we create to hold the trauma may last a long time. At some point, perhaps after another traumatic event or just the normal wear and tear of life, those internal containers break down and we have symptoms that may not make sense in the context of our present life. Chronic pain, nightmares, disassociation, mood swings, inappropriate anger, inability to focus and function may all be the result of old traumatic experiences that are leaking into the present moment.
I have had many clients come to me in their middle years thinking they were crazy because of the onset of such symptoms. The unconscious mind does not distinguish well between the intellectual concepts of past and present. It is pretty much all happening now in that part of our mind and so the symptoms make sense in that context. Finding ways to process and release the trauma is what clinicians have been studying for a long time. EFT, TAT, hypnosis, Somatic Therapy, and EMDR are techniques that can be helpful in finding safe release.
Prevention beats cure. Allowing a few minutes to “shake it off” before moving on can facilitate the natural release of a traumatic experience. Give permission to yourself (and others) to cry, tremble, vent, shiver or shake in the aftermath of a traumatic event. It may be uncomfortable to experience or witness the release, but the alternative of trying to bury it prematurely can have really unpleasant long term consequences. There are of course times when it is not possible to take time to process (in the heat of battle, childhood abuse) and professional help may be needed to release those experiences safely.
For more on this topic: Why Zebras Don’t Get Ulcers by Robert M. Sapolsky