Excerpt from this article:
Those who have spent more than a few passing minutes on Facebook could attest to the fact that marriage is usually portrayed in an exceptionally positive light, more so than other areas of our lives. There is far more social acceptability to not only grumble but to seek input about the missteps in our careers or the sleep deprivation that goes with child rearing than about the possible fissures in a marriage.
…So why does the social media screen tend to go dark after the wedding, only to light up with the occasional burst of good news? Perhaps Facebook is actually mimicking the real-life personal dynamic, where once the vows are exchanged, the marital code of silence goes into effect: The oversharing culture, which reigns during the engagement and wedding, suddenly morphs to undersharing about our spouses. Maybe there’s not as much of a highlight reel to show after the honeymoon when real life sets in.
It has to do with vulnerability, said Sherry Turkle, a M.I.T. psychologist and author of “Alone Together: Why We Expect More From Technology and Less From Each Other.” “If you complain about your pet, your job, even your children, there is a sense in which these are external to you — the complaint is about what life has dealt you,” she said in a phone interview. “When you complain about your marriage, the boundary between marriage and the self is much less firm.”