This fic will make sense if you've listened to Torchwood's new radio play, Submission.
'The night is dreary,
He cometh not,' she said;
She said, 'I am aweary, aweary,
I would that I were dead!'
-Mariana by Alfred Tennyson
When he was very young, before his father started to alienate his 'odd son,' Ianto had asked to go scuba diving with him. The idea of swimming in the deep, in the ocean, a place which humans knew so little about, fascinated him. He wanted to swim down and soak up the knowledge that the sea held, learn the secrets held inside the waves.
His father's lips had squirmed into a wry, tired smile. "Not today," he'd answered. "No money. Maybe in a few years, if I ever get that bloody promotion." Then Rhiannon and Mum had stormed in from a shopping trip, bickering, and Ianto's father had gone back to the wooden, condescending man he would come to know.
Now, Ianto was pretty sure he'd had his fill of the deep for a while. He didn't want to go into the water and think of Sam or Henry, or the frightening memory of Carlie possessed by that alien, egging him on, telling him in a cruel, pleased voice that Jack cared more for Gwen than he.
It was amazing the things Torchwood put you off of. There were so many things he'd wanted to do as a child, and now he knew he'd never want to do them, ever, because of some memory Torchwood had put in place of the eager excitement of anticipation.
He no longer wanted to scuba dive. For a few days after the incident, even though it went completely against his usual nature, he barely wanted to bathe for fear of hearing that awful scream, that creature using Carlie's voice.
It hurt, though, the creature's tale of it's mate. Because he knew that one day, that would be Jack. That one day, Jack would leave him, leave Earth. And he knew his Captain would look back, look down, and see everyone he'd ever known, the memories of them, screaming. He'd see all of their faces, the ruin in them, the gutted feeling of loss. And Ianto knew that despite the fact that he would go on, part of Jack's mind would be trapped in with those memories, forever.
He only hoped that one day, Jack's heart would someday get the confession and forgiveness, the final act he needed.