Does cycling solo make you nervous?
No, I have been cycling for so long there isn't anything I haven't seen or experienced.

When you're by yourself out in the middle of the country, miles from the nearest town ...... do you feel any twinges of apprehension?
Again, no. I like the serenity and tranquility of riding alone, especially early mornings when no one else is in their cars and everything seems cleaner and fresher.

Do thoughts like these drift through your mind:
--- "What if a dog (or other animal) attacks me out here?"
Most dogs appear meaner that they actually are, and are willing to play or simply go away if commanded to. Very rarely will you find a dog that will simply attack you as a bigger mammal.

--- "What if some drunk hits me?"
This could be a problem depending on where you are riding and at what time. But if you were really concerned about this you would never leave your home.


--- "What if some redneck driver or gang of teens starts to hassle me?"
A cellular phone come in handy here. Sometimes the mere act of taking one out of a back pocket will send most bullies scurrying away.

What about when you ride alone at night? Do you experience any feelings of fear at what you might encounter out there?
I do not ride at night, no particular reason other than I have familial responsibilities and I can't see well enough with any type of bicycle headlamp.