I visited an old friend in Birmingham last weekend, by old I mean long standing, as she's younger than me and I don't consider myself old yet. We went to university together and shared a house with three other people who are all still close friends too. I suppose you do quite a bit of growing up together at that point in your life and there is a certain intensity sharing a home, and being part of each other's daily life. Those days were fast and long, slightly chaotic and exciting so you don't know if the people around you will always be in your life, in fact I don't think I considered it until it was time to leave.
We watched the recent Madonna interview on catchup one of the evenings and she talked about how we are brought up to believe that family means blood, but actually we create new families for ourselves, people who won't judge, who you can trust, people who are loyal - that's family.