I deleted my Facebook account 5.5 years ago.
It continued spamming my e-mail address associated with Facebook, so I used its unsubscribe feature to unsubscribe from its notifications.
It did indeed seem to unsubscribe, but today, more than a year after unsubscription, Facebook sent me a suggestion of a friend that was indeed someone that has been a close friend, and someone that I only knew after I closed my Facebook account.