Facebook as stalker ex: When you stop logging in, it incessantly, desperately emails you to lure you back

After switching computers and phones, Henry Grabar tried not logging into Facebook for nine days; the company's systems noticed and embarked on a relentless campaign of email harassment, automatically emailing him with algorithmically created enticements that were supposed to make him so curious about what all his "friends" were getting up to that he logged back in. (more")