As I am sure you know, Facebook offers no way of knowing who has stopped being your friend. You only know about that when you want to check the profile of that person, and find that he or she has ceremoniously dumped you. Irritating? You bet. And it would be nice if Facebook offered one way or the other of knowing when that has happened, so that you are not oblivious to the whole situation. Because (like it or not) Facebook has redefined the concept of friendship. When someone dumps you there, it means much more than just losing a contact from a list. The sooner you get to know about it, then the simpler it will be for you to deal with what has happened.
Well, until that day arrives we all can turn to this plug-in. As its name suggest, it can check who has unfriended you recently, and notify you about it. Both those who have Firefox and Internet Explorer will be able to get FriendsChecker to work, and they will be able to do so for nothing – FriendsChecker is free from start to finish.
FriendsChecker.com In Their Own Words
Find when someone unfriends you!
Why FriendsChecker.com It Might Be A Killer
As incredible as it might sound, Facebook fails to inform you about these friends who dump you. A service such as this one is nothing short of vital until that is seen to.
Some Questions About FriendsChecker.com
What else can this be used for? 
