Private life is built without regard to reputation making. When you read on a social network what someone had for breakfast you are learning nothing private. Your reading is part of the act of reputation making. Even if you are given intimate details, because they are intended to be part of a public reputation they do not reveal private life. Private life is privately intended communication, defined as what did not have to pass through the prior filter of rejection or acceptance based on probabilities, on show making, on proving yourself as competent in one role or another. What I write about myself is public. In reading you will not understand my private life, you are not meant to understand my private life. You have not been invited.
Public life and private life are mutually destructive. If you attempt to force on the world what you know to be true from experience of private life, you put yourself in danger. If by chance you have learned to do something in your private life that is acceptable to public life, your ability to teach your family what you have learned in private experience will be endangered by the competing public way of speaking that is based on show making and probabilities. You will have less chance of properly educating your children in what is important than someone with less public exposure.
But private life and public life can be kept separate. That is one thing the new social media are teaching. On Twitter you have followers, not friends. You make a reputation. There is not even the beginnings of private life. If we learn from seeing this what private life is and begin to protect it, we'll have gained something valuable.