How to Tell a Deactivated Vs. an Unfriended on Facebook
If you have tons of Facebook friends, you may not notice when one of them falls off your friends list. It could be that he unfriended you; it could be that he deactivated his account, or he may have blocked you. While Facebook keeps you from discovering certain private details of the state of other users' ...
If you don't see him, then his account has become inaccessible to you, either because he deactivated his account or because he blocked your account. Step 5.