Actually "phobia" means fear in Greek. And English people tend to use by this definition,
"usually defined as a persistent fear of an object or situation in which the sufferer commits to great lengths in avoiding, typically disproportional to the actual danger posed, often being recognized as irrational."
So with the number of bikers you see on the road locally, and the number of accidents you hear happen locally, could you perhaps define that your fear of being run over being nearly the same type of phobia as people being scared that every spider they come across will bite them and kill them?
Never let down your guard when biking, but always remember, most of the fear itself is not rational from a statistical standpoint. Relax, and try biking on the roads slowly as you build confidence, but giving up is not a solution.
Jim