The Doctor leans against the console and sighs; his impossible girl's gone and he's alone.
Her laughter as been replaced by the TARDIS hums and his conversations with himself.
The absence of her bright smile and the innocence and wonder that sparkled in her eyes has left the TARDIS dark and cold.
The memories of very spot she stood on, every secret she shared, every squabble some silly, some serious and some he still doesn't understand, her many attempts to hug him, her anger, her patience, her forgiveness and love still linger.
The Doctor really isn't surprised that she left he knows Clara isn't t the first companion to leave and she's not the last, either.
In the end they all leave despite the promises of forever they make to him, it hurts but he moves on he has to.
But loneliness has a funny way of setting in when he looks around the empty TARDIS and his tears start to form.
He looks up as the tears stream down his face and wonders when will it stop hurting so much?