Nothing anti-social about that. I do most (probably 95%) of my riding solo. I do a lot of photography and I really enjoy being able to stop and talk to some of the people that I meet along the way. Old stores with a 'gossip bench' out front are like a gold mine to me. I like hearing the farmers talk about crops, other riders discussing their rides, or hikers talking about trail conditions. A bike gives me a great way to do that, but the constant stopping and going isn't conducive to group riding. Out of respect to other riders, I try to keep it in check when riding with a group. I also like to crank it up occasionally, pushing hard for a few miles before settling back into a more comfortable rhythm.
I'm primarily a backpacker and hiker and often spend a couple of weeks at a time on the trail alone in the northern Rockies or our local Smoky Mountains. It's hard to find people that can adjust their schedule to mine, and even harder to find others that are willing to backpack through grizzly country - my favorite destination. I like the freedom of being able to wake up in the morning and choosing to stay in a good backcountry location for a few more days, or to move on to something new without having to worry about upsetting the schedule of a group.
At the same time, I really like the group get-togethers that we have from time to time. When I attended the recent Vee gathering in Tellico Plains, the riding was secondary to me - I enjoyed meeting the other riders, seeing their bikes and riding with them across the Cherohala and the Dragon. It's a good mix, but I realize that my usual style of riding isn't suited to other riders. One's for fun and socialization, and the other is for recharging. We had a good system that accommodated all of the riding types for that one - we would agree on stopping points and then split up with each rider riding at their own pace to that point. On the return trip, we each took our own routes - some did a long loop, some wanted to ride the Cherohala again, and I hit the dirt roads back across the mountains. It worked out good for all of us.
Several years ago I attended a management training course at a local community college that was required by the company that I work for. I usually hate those things - lots of rah rah meaningless crap that is mostly designed for making the attendees feel like an integral part of the system. That one was different. We studied the two different psychological makeups that most people fit into to some degree or other - extroverted or introverted. I had always thought that introverted simply meant that a person was anti-social and that an extroverted individual was usually happy and a 'people lover'. Actually, the definition is quite different. An extrovert gets the bulk of their input from outside - they need constant company and are usually unhappy if alone. They are more likely to be comfortable in crowds, such as parties. Often, they aren't avid readers, preferring conversation instead. As a rule, they prefer a the movie to the book, the opposite of the introvert.
Introverts gain their input from within and aren't as likely to need constant outside input from others. As a rule, they don't enjoy large crowds, loud parties, etc., preferring instead smaller groups of close friends. They're more likely to be avid readers, and often are hobbyists, doing woodworking, painting, old motorcycle restoring, etc. - mostly solitary pursuits. Most of the hardcore backpackers that I know lean heavily towards being introverted. I do - the instructor at the seminar said that I tested higher as an introvert than anyone that she'd tested in the past. I'm perfectly happy being alone in the wilderness for weeks on end. Give me a good book and a couple of hundred miles of trail and I'm happy to forget about the outside world. I've been on 5 week long road trip/backpacking trips in the Rockies where I'd never check back in at home for the duration of the trip. I love that sort of freedom (and I'm lucky to have a wife that understands how much I need it.)
Neither is bad, and most of us are a combination of both personality types. Being one or the other doesn't mean that you'll be happier or more unhappy - that depends on a lot of other factors. Chances are that even though you prefer solo riding, you still enjoy hanging out with other riders, talking gear or favorite rides. I'm lucky in that the two people that I ride with the most have riding styles that are a lot like mine. I'm always very comfortable riding with them and look forward to our rides.
The historical image of the motorcycle rider is a lot like that of the cowboy - a lone rider, the rebel, etc. In recent years though, it seems that group riding has become more and more popular. I guess that what it all comes down to is that we're really lucky to have the choices, the time and the opportunities that we do.