It's much easier said than done. To the degree that you can leave the awfulness of that day behind I salute you. Nothing remotely close has ever happened to me. None of us know for sure how we will react, and endure, when tested. From where I sit your ability to find some perspective is remarkable.
My father, who was a difficult and tormented man, nonetheless taught me a few things. Among them is the difficult-to-accept fact that our ability to alter events is quite limited, and to control them, impossible. His eldest son was born brilliant but damaged in a mysterious and relentlessly enervating way that an endless parade of shrinks, health gurus, rabbis and charlatans could not repair. He began running away from home at 16 and he never stopped. He never worked much, and he never married. Now 65 years old, he lives alone a one bedroom somewhere in Brooklyn, blaming everyone but himself for his troubles, pushing away everybody who might have cared for him.
His youngest son, your faithful correspondent, was just born lucky.
Children end up more or less who they're meant to be. At least I believe that is the case. Our job as parents is to shield them (for a while) from harm, to allow them to fall but pick them up when they stumble, to not get in the way, and to tell them the truth. From what I know, that's a pretty good description of exactly what you've done.