It's already been said, but, seriously, there's no excuse to hurt your dog. None. This sort of behavior reflects poorly on all of us with Post Traumatic Stress Disorder. If your local media discovered this, and decided to air a story on this, surely, the headline would scream, "Next up at 5 O' Clock, local man with PTSD abuses dog."
You need to accept responsibility for your actions, you don't have the right to hurt any living thing because of your pain. Yes, pain, it sucks. But that's what makes us survivors. Carry this cross with dignity. Do not, hurt others.
Get a punching bag, get in therapy, get in therapy a coupe of times a week, own your behavior, and turn the animal over to a shelter.
I appreciate, you reaching out to a community of your survivor PTSD peers. I appreciate, you being honest, and I hope you can get the much needed help you need. But, please, get something like a punching bag, and whale the sh*t out of it the next time you have the compulsion to abuse anything, living.