Shouldn't that be your husband/wife/partner?
What is a best friend anyway?
Somebody 'Else' ?
How do we recognise them?
Is it the way that they make you laugh and the fact that you love the way they do?
More than just the shared sense of humour?
What does that include then?
Similar (if not exactly the same) hobbies?
Mutual appreciation?
Attraction?
Goals?
Respect?
Interest?
Habits?
All of the above?
Well, when you find someone like that, I guess you'd know.