What a terrible tragedy. I am so sorry for you and her whole family. It’s no wonder you feel awful in a million ways. But please don’t feel guilty – no doubt her brother feels guilty enough. (He never should have driven under the influence, yet I feel for him, too – his horror will last a lifetime). You may want to tell her grieving parents how much you loved her or write a letter about what she meant to you. You could also make a scrapbook about your friendship and give them a color copy. Time doesn’t heal, but it helps. Though you’ll never forget your friend, little by little your grief will lift.