That is terrible! But it is not your fault.
Accidents happen.

My second cat was hit by a car in the night, after i shooed him away from me because i wanted to sleep and he wanted to play. It took a while to stop thinking that if only i had played with him a bit, he would not have gone out, and get hit by a car.

But that is not how the world works. Accidents happen. you cannot blame yourself and definitely cannot make the world perfectly safe.

❤️