Getting in an accident like that can cause some psychological setbacks. I think it's natural you're having second thoughts.
I got hit on my bike when I was in college waiting at a stop sign. I truck was turning and hit me headfirst. I don't remember getting hit- I just remember waking up laying on the ground and having to be restrained by other people when I tried to get up so I can make it to registration before I got shut out for next semester's classes. I didn't ride for years after that, and to this day, I don't even know what happened to my bike. I didn't ride for years afterwards.
I just got back into cycling a little over a year ago, and I wished I'd just mustered up the courage to get back into riding sooner. I really did love riding, and I don't regret getting back on the bike and starting all over again.
Take it slow and get back on the bike, and just start small- I bet if anything, you probably have an increased awareness of your surroundings, and this will make you more aware of cars and such around you that may be invading your personal space. Take advantage of that.
Good luck with all that.
Koffee