He came home to find her laying on the floor on the red rug she must have just bought in the last couple of days.
Her legs were propped up on a chair, empty bottle of firewhisky at her side.
She didn't even notice him arrive.
She was singing Blue Christmas and tears were slowly falling. Shooting color changing charms, as all of the tree and room decorations turned blue one by one. He was actually impressed with her accuracy, with how drunk she must be to let herself get to such a state and judging by how blue the room was, she had been at it for a while.
"A blue christmas, indeed."
She didn't even look at him. She didn't pause her singing or in any way acknowledge that she had heard him.
Maybe she hadn't.
How he wished he could scoop her up and take away her pain. He had lingered after his death and had been to see everyone but her, saving the hardest for last. He knew he was lucky to have had the years he did have after she saved him in the Department of Mysteries. He could not regret anything he was so very grateful for. Borrowed time always comes with an expiration date, after all.
Sirius noticed she had stopped singing and was just looking at him. Unblinking, the room finally completely blue except for the very red rug.
The room was silent, as the red began to move beyond the rug. He realized, to his horror, he was so very wrong. The rug was the same white one she had bought when they first moved into the cottage.
Now, he knew he needed to move on. She would be waiting for him, after all.