Long enough to accept it. Lots of reasons that ultimately add up to being an inadequate person, but also no transportation/income in a semi-rural area (also health/personality issues) so I'm a shut-in and thus don't ever meet people. That said, even in school/college it's not like I ever really made strong connections with people, romantic or otherwise. Non-religious in USA (esp. given rural) certainly doesn't (and more so didn't) help with a dating pool either.

And even if none of those were issues, I'm just not that interesting. I suspect the people who would like to be around me are probably in their house more-often-than-not, and not within any distance/likelihood of meeting.