PTSD is another kettle of fish... but without as much negative emotion, then PTSD is no longer fed as much, hence symptom reduction.
That reminds me of this old Cherokee Legend:
An old Cherokee is teaching his grandson about life. One evening he told his grandson about the battle that goes on inside people.
He said, "My son, the battle is between two wolves inside us all.
One is evil -- it is anger, envy, jealousy, sorrow, regret, greed, arrogance, self-pity, guilt, resentment, inferiority, lies, false pride, superiority, and ego.
The other is good -- it is joy, peace, love, hope, serenity, humility, kindness, benevolence, empathy, generosity, truth, compassion and faith."
The grandson thought about it a moment and then asked, "Which one wins?"
The old cherokee replied, "The one you feed."
Never thought about it that way before, but PTSD is kind of like that, except, you don't have as much control over what it is being "fed" as you would in normal circumstances. It is kind of self-feeding, and a person has to find a way to release the emotions that are feeding it, in order to heal.
The more you heal, the less (I don't think evil is really appropriate, lol) the negative, or less life enhancing one is being fed. It also feeds at the expense of the energy of the person who has it, because so much energy is being expended due to the PTSD, it's effects, coping with it, holding the unresolved emotional energy etc., that you do not have as much "good" life enhancing energy to use in the present.