40 Years Without Human Contact

Smithsonian magazine tells the story of the Lykov family, which lived for 40 years in Siberia without having contact with any other human beings (h/t nc links):

Things had only got worse for the Lykov family when the atheist Bolsheviks took power. Under the Soviets, isolated Old Believer communities that had fled to Siberia to escape persecution began to retreat ever further from civilization. During the purges of the 1930s, with Christianity itself under assault, a Communist patrol had shot Lykov's brother on the outskirts of their village while Lykov knelt working beside him. He had responded by scooping up his family and bolting into forest.
That was in 1936, and there were only four Lykovs then—Karp; his wife, Akulina; a son named Savin, 9 years old, and Natalia, a daughter who was only 2. Taking their possessions and some seeds, they had retreated ever deeper into the taiga, building themselves a succession of crude dwelling places, until at last they had fetched up in this desolate spot. Two more children had been born in the wild—Dmitry in 1940 and Agafia in 1943—and neither of the youngest Lykov children had ever seen a human being who was not a member of their family. All that Agafia and Dmitry knew of the outside world they learned entirely from their parents' stories. The family's principal entertainment, the Russian journalist Vasily Peskov noted, "was for everyone to recount their dreams."
The Lykov children knew there were places called cities where humans lived crammed together in tall buildings. They had heard there were countries other than Russia. But such concepts were no more than abstractions to them. Their only reading matter was prayer books and an ancient family Bible. Akulina had used the gospels to teach her children to read and write, using sharpened birch sticks dipped into honeysuckle juice as pen and ink. When Agafia was shown a picture of a horse, she recognized it from her mother's Bible stories. "Look, papa," she exclaimed. "A steed!"
But if the family's isolation was hard to grasp, the unmitigated harshness of their lives was not. Traveling to the Lykov homestead on foot was astonishingly arduous, even with the help of a boat along the Abakan. On his first visit to the Lykovs, Peskov—who would appoint himself the family's chief chronicler—noted that "we traversed 250 kilometres [155 miles] without seeing a single human dwelling!"

The whole story is fascinating.  Apparently, one of the daughters still lives out there by herself.  I may not have much in the way of social skills, but I pretty much have to have more than those kids.