"So many people today feel alone in a city, surrounded by millions of people. Why is that happening?"
Marshal Brain, the creator of HowStuffWorks.com, points it out in his website on deciding to be better, that according to a research on happiness, the people who classified themselves as 'very happy', differed markedly from average people in just one principle way: a rich and fulfilling social life.
It's indeed a great problem, which we may not see unless we solve other problems, but is at the core of what deep sharing of minds must be about. The ideas of "love"，"happiness", "connection", "friendship", "empathy", "sentience" appear to be extremely important to the quality of our life experience.