It's a little piece of home, and that's better than nothing. That's all he has left in this shattered existence that is now his life. He'll hold it close, even though it's a painfully sharp reminder of all that has been lost: the TARDIS will be the crowning glory of the little kingdom that he will reclaim.
He will piece together the shards that he has lost, and when he finds them they will cut at him and he will bleed guilt, but he will not falter. He will embrace the pain, and let it pass through him until it has gone. All gone and he is left, alone and content and alive.
Decades ago, he fixed the chameleon circuit, but it will be crushed beneath a firm boot now. He will reduce it to its component molecules and release its remains into the junkyard on Totter's Lane. His head will be bowed in remembrance, but he will be quick to leave that place.
The sonic screwdriver, his old friend, will be rebuilt, better and stronger. It will shine brightly to light his way, and emit wavelengths sharp enough to be the calm blue of his home. His fingers will grow accustomed to the grooves of the metal, and he will develop an affection for it. Keep it close for crises and reminding himself how endearingly eccentric he should be.
Once, he will try to construct K-9 Mark IV, but the reality will be too close to memory. "Doctor Master!" the creature will plead , and he will throw the half-finished life into space, sending it tumbling towards a nearby sun.
Sometime, long ago, there was a manic smile that had faced down danger and death and hopelessness. He will take it and paste it onto his new face and it will be a good mask. The fit will be near perfect, and there will be no one left alive able to see through it.
He does not remember being alone often, and so he will seek a companion. Someone eager to share the adventures of space and time, a girl, one from Earth. She will be loyal, but headstrong. She will be trusting, but independent.
He will mould these pieces together and he will have his kingdom. His reality.
He will be the Doctor.
He will be loved.
There are pieces of him scattered across the universe. There's innocence, there's hope, there's patience, and compassion, and understanding.
But here he stands, the pale reflection of his adventures.
Tomorrow, he will begin his work.