If I Unfriend Someone On Facebook Will They Know
Unfriending
When an additional user unfriends you, you not show up on her friend list. If she has actually elected to conceal her profile material from non-friends, you may be unable to see parts of her account that you previously had access to. Even if you could still see her account Wall surface, you will no longer be permitted to upload anything to it once you are no more her friend on the site. The reverse is also true-- a person who unfriends you may no more publish brand-new web content to your Wall.
Notifications
Notifications are a means for Facebook to communicate with a user when there is brand-new activity associated with her account. While you are notified of practically every brand-new activity a good friend takes concerning your account-- such as sending you a message or publishing on your Wall-- unfriending is one of minority exceptions. You will not get a notice, either on your Facebook Wall or by means of email, when a person unfriends you.
Reciprocity
When among your Facebook friends unfriends you, she disappears from your friend list just as you vanish from hers. Due to this reciprocity, you could search your friend list for friends that you suspect might have unfriended you. If somebody no longer appears on your friend list but you see that her account still exists, she has unfriended you.
Considerations
Just because a person vanishes from your friend list does not indicate she has actually unfriended you. It is feasible that the individual has deactivated her account, or that it was disabled by Facebook for one reason or another. If you were unfriended as well as intend to reconnect with the user, you can still send her a private message or request her friendship again utilizing the proper buttons on her profile page.