You've received some good advice here. I echo the advice to do a practice run once, with the pepper spray. Maybe you can find someone to ride with you once, to test it out?
I do a lot of rides early in the AM (5-6), and I used to commute at 5:45. While there were never any sketchy areas on my commute, or where I ride now, some of it is a bit country-like. I find myself doing my fitness rides at that time, in the area of the center of town, as opposed to other loops that would be the same distance, but more isolated. I've never had a problem, and am always amazed that no matter how early I am out there (4:45?), I always see other riders. Two days a week there is even a large group ride that follows part of the route I am usually on. They whiz by me, but are always super friendly.