The term best friends or anything similar is too fragile. People come and go. Some stay longer, some are there when you’re doing well and leave when you’re struggling. Of course these aren’t real best friends or friends at all.
Some friends hang with you because they feel good around you, while others need something from you – either emotionally, monetarily, or because of your relationships/connections. Some of these people become good friends, maybe best friends at last. But what truly tests your friendship are times when you guys travel together; when money is involved; and/or when you guys have heated, intense arguments and have to deal with each other when angry.
If you guys call yourselves best friends, yet haven’t gone through any of these situations, then maybe your relationship isn’t that solid after all. Maybe it’s time to reconsider the term “best friends”.