The reason why is because the author wants us to see how to accept change rather than falling out this is because now these day many people feel the mood not to like this person just because of judging on what they look like or there personality so i like the quote 'we think we know our friends' giving connotations to know them personally . Therefore we understand that it is better to have happiness rather than the anger and guilt of loosing a friend we truly like. hope this helps :)
