I am soo sorry that you are going through this. Understand that there was no way to avoid it. Things like this do happen. About six years ago I hit and killed a cat while driving. It ran out from nowhere and it was horrible. From that point on, I became a vegetarian. Something changed inside me about eating meat.
Try to take something like this horrible experience and make it into something good. Donate some food to a local shelter, or whatever it is you can do to honor the memory of the cat.
Just make sure to remember that it was an accident. There is no fault. Bad things happen sometimes. My prayers and well wishes are with you as you have so often helped me with your kind words. Take care...
"Do or do not. There is no "try." Yoda