Whenever your friend removes you from his/her friend list you did not know when and why he removes you or block you, in this case there is an Google Chrome Extension which indicates you like a notification that who removes you. This Google extension is free and available for download.

• Download it from Google Extensions site.
• Once it install it shows a Unfriend icon in the menu of Facebook. 
  
• And whenever your friend removes you it indicates it like a notification.

Source: Switched