The serial internet entrepreneur, who co-founded Twitter and created Medium, was turning 50 and feeling detached from friends. Maybe a new start-up could fix that. Williams, Evan C, Loneliness, Mobile Applications, Social Media, Computers and the Internet, Entrepreneurship, Start-ups, Blogs and Blogging (Internet), Venture Capital, Medium.com, X (Formerly Twitter) The serial internet entrepreneur, who co-founded Twitter and created Medium, was turning 50 and feeling detached from friends. Maybe a new start-up could fix that. NYT > Business