In the aftermath of her death from his world, the Doctor decided to run.
He could not hide the world from his bleeding eyes, and he could not hide his bleeding from the world’s eyes. He was a broken man, with nowhere left to go, and that was somehow the truth that kept him flying even after losing what he couldn’t bear to lose. The TARDIS begged for a stop, for a rest, but he kept on flying. All of time, all of space, and he couldn’t stay with himself. Memories of her smile and her laugh haunted him when he dared slow his pace, so he just kept running.
All the Doctor ever seemed to do was run. He ran from the Time War, from his dying people, in a stolen TARDIS. He ran from the woman he loved after losing her, and didn’t even have the courage to let her know how he felt before an impossible distance separated them forever. He burned up a sun, stole its dying breath, to say goodbye, yet he couldn’t even manage to do so properly. All he knew how to do was run.
He knew nothing could last with her, right from the start. She had been that lovely girl, down in the basement, and he had saved her from the living plastic without a thought to the consequence. After saving her, he ran, just like he always did, but he couldn’t stay away. She had that effect on him, the Doctor couldn’t manage to resist coming right back to her. Even when an impossible planet almost caused the end for them, she pulled him right back. And what does he do to repay her? He runs away. He always runs away.
When he regenerated, she never abandoned his new face. She cared for him anyways, and stood by his side once again. Whenever she was in trouble, she trusted the Doctor to save her, and never believed for a second that he would let her down. She made a brave man out of him, because she was something to live for. She never dreamt of leaving him or hurting him, but the Doctor isn’t human. He uses that as his excuse, to hide from the ache doubled by his two beating hearts. Nine hundred years of existence and he has become an overly emotional old man.
She traveled with him until she was brought to her end. She held on to his memory across the universes, and never gave up hope. She was a light in his dark, dark world; she was his only escape from the madness of his Time Lord life. She was a friend, a companion, and a confidant. She never asked for anything more than his company and travel around the stars. She was his irreplaceable, unforgettable love. She was Rose Tyler, the fantastic, brilliant, amazing girl who changed his life forever.
With Rose caught in the turmoil of his past, the Doctor decided to run.