I know I have not posted here for a long time (I visit frequently but have not had time to post). I just want to strongly agree with everything that LOAF said, even though I am one of those guys who also likes Freespace.
The other piece of advice I would give is to avoid doing anything to get caught up in the middle. In divorces, sometimes there is a strong pull to take sides. I have a friend who was practically rewarded by each parent for cussing the other out. Whatever the temptation may be to get caught up in that, don't do it. It will tear you apart.
Right now, you need to take care of yourself and recognize you need some time to think and feel in a safe way. That doesn't mean numbing yourself out. Stay away from the weed and the booze, that won't help. Odds are that will only make things worse. Find people who care, spend time with them, and stay out of the divorce. Don't give up on your relationship with each of your parents, but let them know you are not interested in hearing any trash talking.
Listen to yourself, to what you really need. When you need a friend, talk to a friend. When you need to cry, cry. When you need a distraction, find one, but chose one that won't hurt you or other people. When you have questions, ask them. When you need time alone, take it. Listen, really listen to yourself. And when people offer help, don't be afraid to accept it. You have my sympathies. You will make it through this as long as you don't give up. There will be bad days, and I doubt you will ever be happy that this happened, but things will get better.
You are not losing any relationships here, the relationships are just realigning. Remember that. There will be changes, but people are adaptive. Focus on what you can control, and chose wisely those things that are yours to choose.