I have several people who I consider to be my best friends...
One is the person who I do everything with and everyone knows us as best friends. We've been best friends since the day I moved to Ohio, a little more than 7 years ago.
I met one of my other best friends about 7 years ago as well. We weren't as close then, but we've gotten closer in recent years.
My best guy friend and I met about 2 1/2 years ago and have become very close over the last few months.
And my aunt is my best friend who I know I'll never be able to get rid of, lol. I guess we've been best friends since we were about 2, when my grandparents took her in as a foster child.