New answers tagged friends
Another option for finding out who unfriended you is the FB Purity browser extension. It also has a built in deleted friends notification system, that alerts you if any of your friends remove you from their friends list.
Not sure if this is good enough for your use case, but i guess you could always add extra tagged people in a comment on the original post.
Ask them. If they're really your friend, they will tell you the truth.
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