Forgive my deep depression

Today, for almost an hour and a half...I recited the most disturbing series of flashback memories within my system.
They consisted of the very clear, extremely painful frames of the incident in which my dad forced me to help skin alive, torture and butcher my first pet rabbit. It was excruciating like pulling a pin from a grenade and smothering it within my chest.
Startling was the clarity of the images, the ease with which I heard my father's nonchalant voice and the feel of things that were done.
No, I'm not like you. Yes, I've been seriously damaged and horrendously scarred.
At the end of session, my clothes were close to soaked with tears. I heard my therapist cry and choke back tears, swiping handfuls of tissue and responding to my queries with thinly veiled, sobbing answers.
Everything has changed.
The memory that has haunted me since I was a girl of eight, wrapped like a constricting thick chain strung round my chest, no longer consumes me from the inside out.
The air between therapist and me, likewise, has changed. As she is the first and only human to hear of this most violent experience, there is some type of bond, I guess, for lack of better word. She bared witness to a deep, dark, lurking, blood soaked and horrendous incident. No one else has ever done that. The very air and energy in the therapy room changed and we were no longer strangers both doing their job well.
The hours that have passed...the processing...has brought much to bear. Mostly, I'm deeply saddened, my heart filled with grief.
After the incident, in the middle of the night, laying awake, stunned and heartily traumatized, I dressed for school in the morning having to behave as if nothing had happened. Having to look surprised as my brother ran in stating Snowballs cage was open and he was gone. And I walked to school pretending, stoic.
I don't know how I lived..through the event, through the next day, through seeing white rabbits, all with the memory solidly embedded, in its entirety, within my chest. I was 8 yrs old for God's sake.
And I weep for the child me that had to hold Snowball down, that had to use the knives thrust into my hands, that saw and readily felt Snowball's fear and pain. No, I'm not okay and I don't expect to be...for awhile.
There are a handful of egregious events that thoroughly impacted me...this is one.
Poor, innocent Snowball.
Poor, innocent me.