Very Effective!
I have to say you did an amazing job of drawing me in to the eerie, fear filled darkness and the remarkable transformation from fear to hate. Absolutely love that you went in that direction. It begs a deep question about trauma and the cycle it seems to perpetuate.
Your imagery was intense in some places, and very well done. I particularly loved your shadow description: "Some of these shadows danced, others fidgeted nervously as if the darkness were their only true friend, some appeared to hide, receding into the dark night, but one of these shadows took form, breaking out of the shadow realm and smashing into reality." This really created a surreal sense which was fitting destroyed by your harsher word choice at the end.
There were a few spots--especially during the hunt of the deer--where I tripped over a couple sentences and was jarred out of the story and back into my chair. Some just felt awkward enough to make me do a 'back up and try again'. A few spelling mistakes (or more likely, typos) had the same effect, especially where you have "latter" instead of "later".
Beyond that, I really enjoyed the ride and hope you keep going with this! You did an awesome job of setting up the characters too (Jimmy's metamorphosis is my personal favorite, even though it makes me shudder).
Read the story now