"Obsession", her mother had called it.
All the hours she put in at Torchwood, day and night, to help build the Dimension Cannon. She wasn't "eating enough", she wasn't "sleeping enough". But none of that mattered because with every moment she spent on completing the machine she was one step closer to finding The Doctor.
The night before the first jump Rose passed by a clothing shop on the way home and stopped at the sight in the window. The jacket was leather like the one her first Doctor wore, yet blue like his eyes which led to the immediate purchase of the garment.
Now standing in the middle of the Torchwood lab, clad in the brand new protective armor and holding the almost fully charged yellow disc in her hand. Rose stared at that godforsaken white wall as she mentally prepared herself for the journey upon which she was about to embark.
It wasn't obsession. It was determination.
She made him a promise of Forever and she was determined to keep it.