I've been commuting for almost exactly a year - 1800 miles - 3-5 times a week.

No close calls to speak of, and only a few honkings of the horns. My wife also worries, but has gotten better the longer I've ridden my bike, but I think she just doesn't tell me as much.

When you ride the same route, you usually figure out where people may not see you, and you can adjust accordingly.