The thing is, G had known intellectually that victims of trauma could have memory problems. He'd studied enough psychology to understand the lingering effects of violence. But it wasn't until months after he was shot that G truly got it.
He woke up in the hospital, tubes piercing his veins and delivering sweet, sweet oblivion, and knew that he'd been attacked. Could remember, vaguely, how Sam had shouted his name and hugged him close while waiting for the EMTs to arrive. Most of G's recall was of agony, the struggle to breathe and the throb of bullet wounds.
Recovery was a long and arduous process requiring patience. G chafed against the restrictions imposed by his surgeons, didn't want to listen to Sam's advice about always taking the meds and doing exactly what the physical therapists told you. Eventually, G was released and began to do as he wished. And what he wanted was to put the entire incident behind him. There was a lurking curiosity about why he'd been shot, why the police and NCIS investigators hadn't found the perpetrators, but G's life was lived by the principle that it was better to move forward than look back, and he set his attention on the future.
Nate tried to get G to open up, to "talk about his feelings," but G would rather walk over burning coals, or go another ten rounds with the physical therapists. He escaped into paperwork instead.
The discovery of the tangled web of petroleum stakes and case history tracing back to Russia, the identification of Alina Rostoff as his one-time foster sister, made him aware of just how many gaps his childhood memory held. He knew it wasn't usual, knew it was strange not to remember anything about where you attended third grade except the name of the school – not the teacher, not the lessons, not the other kids -- but G liked to think he lived in the now and that was enough.
He'd been partners with Sam long enough to be aware of how keenly Sam avoided topics that might cause G to withdraw. For all their teasing and banter, they had firm agreement on how far they could go. G might mention Sam's mom, but only mention. Sam would ask about G's rotating crash pads, but never probe the reason why G got itchy feet if he slept in one place for too long.
The ever-emerging caseload kept Sam and G busy, and Hetty's arcane, tea-soaked demands filled the rest of the time.
G could ignore the gaping holes in his childhood, and fill the blank spots with new experiences with his team. And if Sam's smile meant more than never having a birthday card, G didn't have to tell anyone. He could just save up the moment, and ensure this was one he never forgot.