It's inevitable, this question. He's been waiting for it since she came here and realized just how much had changed: that they'd been together, and that they weren't now. The sheer impossibility of that has clearly eaten at her.

And yet, he hasn't come up with a way to say it. What happened is everything and nothing, too earthshaking to be contained. More importantly, he hasn't wanted to think about it, and so he hasn't. She'll hear it, and she'll understand herself, and maybe that'll get her home - and he'll be alone again.

The best he can do, after a pause, is, "I drove you off."