The dictionary defines 'friend' as "a person whom one knows and with whom one has a bond of mutual affection". A bit further down there is another definition: "a contact associated with a social networking website".
One reason I recently deleted my Facebook profile was that having so many "friends" on Facebook was turning everybody into a contact.
I began to recognize that in the name of simplicity, social networks are severely degrading what it means to have 'friends' and that they're slowly, friend-by-friend, psychologically training us to believe that 'friend', 'contact', and 'acquaintance' are all same. They're not.
Friends are more than contacts.
(Note that I haven't entirely abandoned Facebook: I'm still sharing my work through my Facebook Page.)