I’ve said before and will say again, I love the Doctor and River, I love everything about them, but there’s something special about Let’s Kill Hitler. In some ways, I think it shows his love for her better than any other episode.
From the Library onwards, (for him). she knew him, more than that, she was secure in her relationship with him. It didn’t matter if he knew it or not, she did, and that was enough for her. You don’t see River analyzing their relationship or second-guessing her behavior. She just flirts with him and pushes all his buttons.
At first, it seems Berlin is more of the same. Okay, she shoots the TARDIS, but hey, high spirits. And then
: It was never going to be a gun for you, Doctor. The man of peace who understands every kind of warfare, except, perhaps, the cruellest. Kiss kiss.
She’s not just killing him—she’s mocking him. Yes, she gave him a royal scolding at the end of GMGTW, but she was serious then, she was trying to warn him about certain tendencies that could get him in trouble. Instead, she’s calling him a hypocrite, a criminal, heartless with no concept of love.
I was born to kill the Doctor
The Doctor sends Amy and Rory to follow her and staggers into the TARDIS. When he learns about the poison, he factually responds
better regenerate then
Even when informed that he can’t, his reaction is quite interesting, especially if you consider Ten’s panicked reaction to death in Stolen Earth and End of Time. Ten tried to hold out as long as possible, even lashing out at Wilf.
Eleven, on the other hand, is all business. His primary objection?
River needs me. She’s only just beginning. I can’t die now.
Not one word about fair or unfair, nothing about timelines being rewritten. He has to take care of River. Sure, she seems to have things under control, but it’s a self-destructive path: how long do you think she’ll last in the middle of Nazi Berlin at this rate?
But the part that really chokes me up is the Tesselecta scene. I’ve already written about it here. Not only does he defend her, but he boils it down to one simple question. Yes, she is/will/has killed him (not yet, by fixed points.) Sure, she’s been brainwashed. Yes, she’s the daughter of his best friends. But he doesn’t defend her on any of those grounds.
"According to records, the woman who kills the Doctor."And I’m the Doctor. So what’s it to you?
If you look at other places—Power of Three, Bells of St. John—it’s clear what he’s doing here. This is a giant UNDER MY PROTECTION sign, no explanation necessary. Nothing else matters.
And later, when he leaves her the message and she realizes who she is—who River is, because at this point they’re different people—I love imagining what she must have thought at that point, because I don’t think she’d known that sort of love before. Madame Kovarian and the Silents weren’t the caring sort, Amy and Rory were nice but they weren’t her parents yet and couldn’t protect her.
He can protect her. He did. What she did wasn’t even mentioned.
But even then, he’s still giving her a choice. He didn’t tell her that she could save him. He didn’t even hint. He flat-out lied,knowing he could die for real. She wasn’t indebted to him unless she chose to be.
That’s real, true love.