Someone very close to me ODed as well, she was practically my unrelated sister... It's very hard thing to deal with. and there are alot of unawnsered questions I still have... Did she do it on purpose? why didn't she stop? why didn't she call me for help ect? Did she go peacefully I know how you feel I'm here if you want to talk about it. it's been almost 1 year since christiana died to she would be only 19 this year.
Every Christmas I will think of her, as I am sure you will with your friend. Just remember that they are in heaven or somewhere and they are watching over us.... Maby giving his parents a christmas card or call might help you.