He can’t help it. He tells himself the TARDIS is taking him there on it’s own, but deep down inside, he knows he’s the one steering it to that lone, empty stretch of beach. At first he just stands there, looking out at the endless white sand, listening to the crash of the waves on the shore. Even though the beach is empty he swears he can still hear it, the faint echo of her voice, her sad, painful cries. When the TARDIS conjures up an image of her, recorded from that day so long ago, at first it seems like a good idea… just to see her again; that pink skin flushed from the sun, that yellow hair blowing in the wind… but it’s not her. He knows it’s not her, and it’s not just because the recorded sound of her voice sounds slightly tinny. He knows it’s not her because it hurts too much remembering why it can’t be her. So he twists his sonic screwdriver and she fades away, just like he did all those months (years?) ago, and he goes back into the TARDIS and flies away again.
The next time it happens, he only half tries to convince himself it was the fault of the TARDIS. By the third time, and the fourth, and the fifth, he doesn’t even try anymore.
He just wants to see her one more time. There’s nothing wrong with that… right?