We're contemptuous of 'distracted' working mothers. We're contemptuous of 'selfish' rich mothers. We're contemptuous of mothers who have no choice but to work, but also of mothers who don't need to work and still fail to fulfill an impossible ideal of selfless motherhood. You don't have to look very hard to see the common denominator.
As an angsty teenager and college student, I used to mock people who lived in gated communities, who were so afraid of the unfamiliar world they had to erect a physical boundary to keep it at bay. But now I wonder, aren't the boundaries we draw with Facebook just as secure as a man-made moat or an underpaid security guard manning a booth?