In the modern US, we treat privacy as a serious right. Although it is not protected in so many words in the Constitution, several key Supreme Court decisions have been based on the inherent right to privacy as fundamental to American law. (Of course, this is all undercut by the modern tendency to blab all of one's activities and feelings on Facebook.)
Medieval people had no such assumptions about privacy. In a medieval village or a castle, a community of people living close together, it was assumed that everyone knew everyone else's business, perhaps even better than they did.
Even sex was not nearly as private as we think it should be. In a castle or manor house, the lord and lady's bed was in the middle of the great hall, and the servants slept on pallets in the hall around them. (The bed at least had curtains.) A newly-married couple would be tucked into bed together, and although the bridal party would retreat at least partially, they would find it both hilarious and appropriate to shout "helpful" suggestions through the curtains or under the door and "inspire" the couple with naughty songs under the window.
One has probably heard the phrase, "In springtime, a young man's fancy turns lightly to thoughts of love." In spring, a young man for the first time in months had a chance to get a young woman off by herself, in woods or field, away from all the relatives.
One has also probably heard, "Each man's house is his castle," with the vague suggestion that people are entitled to privacy in their houses "just like" medieval lords were private in their castles. But this phrase was only coined well after the end of the Middle Ages, based on a thorough misunderstanding of medieval law. Any medieval lord who defied the king would find the king (and the law) had no concern for or indeed knowledge of any inherent privacy rights. Such a lord's defense would reside in high walls, not in some legal principle.
For that matter, the distinction between public and private which we make for rulers--a president cannot treat the taxes that have been collected as personally his--is also a fairly modern distinction. Until about 1200, the royal treasury, what we would think of as "public" funds, was kept under the king's bed, and he decided how it should be spent.
Religion, which we also tend to think of as a private matter, was also an issue for one's neighbors in the Middle Ages. Someone who had done serious damage to the Church or who had fallen into heresy would be excommunicated, literally cut off from the community, because it was feared that the normal sharing of everything, including religious ideas, would infect the others.