What does it means when someone's fb user name disappear from your list and even when you go to check the messeges they sent it to you,you see the messege without their user name,you can't even read the messege anymore. does that mean they blocked you?cancelled their account? or what?
it's most likely the deactivated account option in my opinion. I see my friends list go up and down daily and that's because people deactivate their account. You can disable/enable your account when ever you like. The data is still kept, only when you delete an account is the information removed permanently.