I actually like riding alone - I can do intervals when I'm by myself, and go as fast or stop åş often as often as I want, as well as go where I want to. I ride with a group every Saturday, and with my DH once or twice a week, so I enjoy my alone time. Fortunately for me, it's very easy for me to get a 30-70 mile ride in and still never be more than 15 or 20 miles from help if I need it. I carry my basic tools, always check my bike before and after a ride to make sure it's in working order, and carry a phone with me (fully charged) I also wear a road I'd. I don't remember ever being worried about cycling on my own, though I did worry about motorcycling alone.

As for the group rides, try to find one that's no drop, or mix up which friends you ride with if possible, instead of one ride with all of them.