Facebook does not have a tool that tells you who has unfriended you, so there is no way of knowing other than guessing.
The solution to seeing who has removed you from their Facebook friends page is a user script called Unfriend Finder, available on userscripts.org.
It sends notifications like other Facebook applications and adds a page called “Unfriends” to the upper-right corner of the top navigation bar.
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This is a third-party application that is not endorsed by Facebook, so install it at your own risk.
1. Install Greasemonkey for Firefox, if you use Firefox. Greasemonkey allows you to install and manage multiple user-scripts, which modify websites using Javascript. If you use Chrome, you can install user-scripts as an extension. You will need to restart your browser after installing Greasemonkey.
2. Go to the Unfriend Finder page on userscripts.org and click “Install” in the upper-right corner. According to the developer, this script also works with Safari, Internet Explorer and Opera. Restart your browser again.
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If you’re using multiple computers to access Facebook regularly, you’re going to need to install the user-script individually on each computer.
3. Open Facebook. Unfriend Finder will make a catalogue of who is currently your friend — it cannot tell you who has unfriended you before you installed the script, but it will continue to monitor your friends status from this moment on.
4. Click the “Unfriends” page link in the upper-right corner. This page shows you who has unfriended you. It also shows you the number of unanswered friend requests — called “pending requests” — you currently have.
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You can also access this page from the sidebar on the left from beneath the “Favorites” header. When someone does unfriend you, you’ll get a notification saying “Person is no longer in your friendslist.”
Final Thoughts
1. If you become friends with someone who has previously unfriended you, they will be removed from your Unfriends page.
2. Unfriend Finder does not work for Facebook pages, only your personal profile.
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