I have what I would consider 3 best friends all of whom I met in college. All three of them were in my wedding, and I still talk to them at least once a week (pretty good considering we are spread throughout the country).
I consider myself very lucky because 2 of them are my big and lil. I was a bridesmaid in my big's wedding and the matron of honor in my lil's.
The other I met through my husband. She and I were both little sister's of his fraternity and he was her "big brother". He introduced us one day, and we were pretty much inseperable after that (I don't know if he knew what he was doing ).