[That hurts more than he can even begin to describe, most of all because he can picture all too clearly how she feels right now. Trust is such a fragile thing, he knows that better than anyone and he'd never even dream of trying to defend what he did. He probably could - it was a private conversation and she caught him off-guard - but he doesn't.
She deserves better.]
I should probably go. [Hesitant. Did he sabotage yet another good thing?]