I was in a similar situation - bought the bicycle and within a year I had lost 40 lbs and was doing great! Then a car hit me from behind doing 50 mph. AND she fleed the scene. Although my body was screwed my spirit was intact so within a year I was back on the bicycle riding to and from work. Then cell phones and the associated behaviours they bring hit the road harder and harder everyday. Now I only ride in residential areas where traffic and speed and commuting drivers are not an issue.
Yikes! I'm going to try to stay on the trails on base and avoid the cars as much as possible.