A side effect of being alone is, of course, that sometimes you don't want to be by yourself. In such cases, I'm accustomed to calling a friend or simply yelling down the hall to a roommate. Here, in a city of a million people, it's not quite as simple. Cultivating a friendship anywhere takes time and energy, as well as a willingness to introduce oneself, ask questions, and make awkward small talk about the weather or the ceilidh dance. I drew a deep breath when I realized that I was surrounded by other students who also felt a wild relief when someone struck up a conversation or thrust a smartphone towards them, awaiting a Facebook handle or phone number. In such a climate, I've realized, friendship tends to snowball in a rather beautiful way. Desperate for companionship, stories we can tell our children, and pristine Instagram photos, we find ourselves wandering streets we barely know with a happy band of ten or more, pushing tables and bodies together in our deli...