I heard about the death of my father in very similar circumstances, truly shocking at the time but I am grateful that he did not suffer.
He was a very important influence in my love of the outdoors and on reflection it now seems quite appropriate that I was out there using the skills he taught me when he died.
I can say nothing to ease your pain, only tell you that it will lessen in time and what you will be left with are the happy memories far more than the pain.
Take care of yourself.