The thing that I respond to most in A Letter To Colleen is the frankness of the time and place. This could have been any suburban home in America. Even though this took place in the early '90's when people wore baggy Jenco's and Kathleen Hanna was getting into fights with Courtney Love; the story of testing out boundaries is timeless. Being young thinking everything at the moment is so important and most importantly making really bad decisions.
Through the grim pessimism of Andy writing a letter that he'll never send. The reflecting back with out the rosy lens of nostalgia, feeling awkward about the eleven year olds drinking beer and a first sexual experience. Andy knows that these were essential moments that make him who he is today. He can never go back and even seeing Colleen, years later, sober and trying to make her way is taboo. Because you can never go back. Sometimes a memory is safer, easier, and cleaner than the present.
Most importantly Andy doesn't regret, while he might hold a flame for a past form of her. He is looking forward. He is out of the sleepy suburban area. Moved on to be with like-minded people in the city. Facing tomorrow.