To those people who spend a lot of time on Facebook, there's hardly a worse insult than someone "unfriending" them. Just think of it: You believe that your new, remote friend is true blue, but then he or she goes and deletes you as a friend. The nerve!

If you're one of those people who loses sleep over this kind of double-dealing activity, then a new app may be just what you need to help you get some peace of mind. According to The Daily Mail, Who Deleted Me on Facebook exposes just which fair-weather friends have deleted you as a contact on the social networking site.

But that's not all: The new app also shows you other stats, like which of your friends' accounts were deactivated or who's logged on at the moment.

The app, which is available for free on iTunes and Android, as well as a Chrome Extension, is the creation of U.K.-based Anthony Kuske. The app previously worked with Facebook, but it was disabled back in February because it was "creating a negative user experience."

The Next Web first reported that the app is back with new features, including the ability to frequently check for new updates. Kuske told Mashable that he strongly believes that the new version of Who Deleted Me won't get disabled because it's getting users' friends lists directly from their homepage, whereas before, the app was getting users' information from the API. In the past few days, the Who Deleted Me website and mobile applications have been experiencing some outages due to an overwhelming amount of traffic

After you install the app, simply connect your Facebook profile to it by securely signing in. From there, it's quite simple to get the hang of. The first screen you see is a list of how many friends you have, and tapping on "view friend list" reveals a page containing lists.

On the top of this first screen is a row of tabs: New, Deleted You, You Deleted, Deactivated, and Current. The app's capable of tracking so-called friends who ended up deleting you from their contact list or those whose accounts were deactivated, but only since you installed the app. When you swipe to the right on each friend on a list, you can delete him or her, too.

Sticklers for exact specifics will feel gratified by the instant snapshot of deletion the app provides, as well. It goes beyond just showing users which so-called friends deleted them; it even exposes the specific date and time that such affronting deletions occurred. Now that's really leaving no stone unturned!

But don't think that this app just tracks those who deleted you. As a bonus, the app also lets you know when you've actually made new friends who may or may not stay around.