To offer an alternative viewpoint, I moved away to a place where I knew nobody and had no existing connections. There's nothing wrong with having social connections with your work colleagues (you spent all day with people in school/university only to want to spend more time with the outside those situations, why is the workplace any different?), and there's plenty of other ways to meet people. meetup.com, sports clubs, pub quizzes, coffee shops, gym. Sure, it's not as simple as just picking up where you left off with friends before you moved, but it's possible, and can be rewarding!