Being a friend is to like a person for who they are, even the parts you don't understand. The reasons you like them makes the things you don't understand unimportant. You don't have to understand, or do the same, or live their lives for them. If you truly care for them, then you want them to be who they are; that was why you liked them in the first place.
Source: Blood of the Fold (Sword of Truth, Book 3)
Contributed by: Karin