Honestly, I have to be careful about road biking by myself too, even though I do it all the time. I'm single and my nearest family lives 300 miles from here, so if I leave a map of my route and the time I should get home, no one will see it and no one will notice I'm missing until I fail to show up for work the next day (or the following Monday if it's a weekend). And if I do have a mechanical or other problem far from home, I can't call anyone to come get me. So mostly I have to stick with routes close to home that are heavily traveled and close enough to take a cab home if needed, even though that means dealing with more vehicular traffic and stopping at frequent intersections. It makes it hard to train for the hilly 70-mile charity ride that I need to get ready for, but that's just the way it is.