I don't generally recommend this to anyone for anything light, but this surely sounds like a heavy situation. Have you considered enlisting the services of a psychologist?
If nothing else, you'll probably be paying a lawyer anyway, and they might be able to help talk you through this. But a psychologist will be better suited to help you work through this traumatic experience. And they're confidential, short of saying you're going to harm yourself or someone specific they're not to tell anyone else what you discussed during the session(s).
Please, for everyone's sake, do not let something eat you up from the inside out.
I have friends that have been through traumatic experiences and having someone to talk to that they trust has really helped. It could be someone that has shared a similar experience, or just someone that can shut up and listen for a while.
As an aside, going through my EMS training we discussed learning to deal with traumatic events. Bottom line is, you need to talk to someone. My instructor told us a personal story of a horrible scene she and her partner were the first responders to. She's managed to deal with it emotionally, hell they even saved all the lives that day. But apparently her partner has decided to kill themself slowly with alcohol because they couldn't figure out how to cope. Friends and career alike long since gone. Don't allow it to happen to you.
I don't know you personally, but I pray you find your way through this.