At one point in the last century, one of my best female friends dumped me like this: She gathered everything I had ever given her or lent her or left in her apartment (books, clothes, presents). She brought it all to a cafe where I was having coffee with a friend and dumped everything on the table, quite officially and publically unfriending me.
I'm happy to say that after 20 years, she is now a best friend again. I just checked definitions of "friend" and "Facebook friend" on Urban Dictionary. Most of the definitions of "Facebook Friend" include the idea that you generally have no connection with them in real life. - I know this isn't always the case, but I imagine being "unfriended" on FB would have less impact than the cafe dumping above.