Was the woman aware that by changing her status, the man would receive a post on his Facebook newsfeed? Did she know how to exclude him from such updates if she had wished to? Did the man worry that he would be publicly humiliated when other people received the same kind of notice on their newsfeed? Did he picture a particular group of people who would see it and was that picture accurate? Do we need to teach children new social skills about dealing with semi-public information online, like the end of a relationship?
There used to be a time when people could quietly signal to their friends that their relationship status was changed and could take certain steps to control who knew that information. At least it was likely to spread relatively slowly, compared to the pace with which it spreads now.
Communication in social networks is unlike our previous forms of communication in some important ways. In some cases that will inevitably have tragic consequences.