I really don't have a best friend. I have a few good friends but no best friend. My best friend in school and I are still good friends (we talk every few weeks) but I wouldn't call us best friends anymore. I am friends with my daughter's friends' moms and we hang out (girls and moms) and that's fun. But no BFF there either!
Quite honestly, since adulthood, I haven't "required" a best friend. I too am a loner. Alot of my friends HAVE to have someone with them to go shopping. Not me, I can shop alone and be happy as can be. But, I'm an only child so I sort of attribute it to that (though in school, I wasn't that way, come to think of it--I always had a BFF). In addition, since having children, I treasure "time alone". I guess I just don't have to have someone with me to do things though sometimes I do miss it. My DD and I hang out and my DH and I hang out (and always have my little man around). Right now, at this time in my life, that's good enough for me!