What keeps me going is my circle of riding friends. I joined the San Fernando Vallley Bicycle Club in 1989. My wife and I moved out of the area for a few years and I sort of lost touch with them. Well, my wife left in 2001 and I sought comfort on the road bike, re-joining the bike club. I have made some new friends and even found some of the old ones still around. Many are faster than me, but riding with them is one of my favorite parts of life.
I think joining a bike club is a great idea. I'm sure there is a big one in San Diego.