I pretty much feel the same way--after two marriages and one long-term living-together relationship. I just can't fathom why I would want to bother again.
Maybe that will change at some point, but right now I can't see it. It's been eight years since the last relationship ended (with one brief paroxysm of "break-up sex" for a couple of weeks with the last guy several months later, and a couple of quasi-dates), I just don't have the energy or need to go out and meet someone. I enjoy not having to please anyone but myself. I think I put out a "vibe" that keeps people at arm's length these days, since I have never had trouble meeting people to date in the past.