The question itself is based on a misunderstanding. The full form of BFF is not associated with "fake friends." It's actually an acronym for something much more positive.
According to established understanding and common usage, the full form of BFF is:
Best Friends Forever
While the initialism stands for "Best Friends Forever," its usage has evolved. Initially used strictly for one's closest friend, it's now also applied to close friends in general. The reference material clarifies this: BFF is the acronym used for the phrase "best friends forever". The phrase was used for best friends, but with time, the usage of the term changed, and it is also used for close friends. Being a BFF of someone does not mean that you are friends with only one person.
In short, there's no legitimate connection between "BFF" and "fake friends." The acronym simply represents a strong bond of friendship.
