No Promises

"You still can't promise me. What if she gets lost? What if something happens to you, Doctor, and she's left all alone, standing on some moon a million light-years away. How long do I wait then?"
900 years in time and space suddenly crowded in on him. Looking at Rose as she tried to reassure her mother. He couldn't take his eyes of Jackie. He felt pinned to the spot.
Looking at Rose, he considered what would happen if he just stepped into the TARDIS and disappeared. He thought about it. Leaving her here, with Jackie, where she'd be safe...for how long. Another 4 years. He knew already.
He'd have sworn Jackie knew too, but that was impossible.
He had to take her with him. Again. He hated himself in that moment. Had to take her with him to save her.
From him.
Sweet innocent Rose. She believed that the familiar feeling between them was...what? Chemistry...kinship?
He couldn't speak. Rooted to the spot by Jackie's icy glare.
He'd wrestled with himself forever before deciding to come back to this time. Selfish.
It was no accident that he met Rose in the basement of the shop that night. She would never know.
Selfish.
If he left her here now, in four years time, she would meet a lanky stranger while sheltering in a doorway during the 2009 terrorist attack on London.
They'd hit it off, and after saving the world again, he would take her away.
And she would die.
Every time he looked at her he lived that moment again. Rose. Dead at the hands of an alien she didn't know existed. He'd taken her away to show her the universe. And she'd died.
Because of him. He'd killed her once already.
He stood rooted to the spot, clutching Rose's rucksack. Hating himself. She'd given him years of her young life. And had died. On some planet a million light years away, and he couldn't save her.
Couldn't promise to this time either.
Hated himself.