It sounds like it is not just ptsd that you are dealing with, but also grief, even complicated grief or even complex, prolonged grief, which is considered a separate disorder to ptsd. I'm so sorry for your loss and ongoing trauma issues!
I can deeply empathize about the trauma and ptsd as I also have complex ptsd and I have grief from estrangement from one of my children, but, to lose your best friends in such a way and in front of you! I cannot even imagine how horrible and traumatic that must of been and continues to be!
Sending sympathy empathy and compassion your way
@Ken