It's diffy, isn't it, because you don't want to seem to kick it back in her teeth. She's (it sounds like, if she's unilaterally revealing interior dialogue) sitting down to at least a crow appetizer here. OTOH, there's the whole "don't scare the deer" aspect, too.
My gut feeling would be, respond (to the best of your ability) as you would to a friend, not a lover/spouse. Not by return of post (how archaic), either. Let her wait for a bit.
I never have seen any percentage in being overly-reticent about your feelings, even in relationship terms, if she's the one fishing. It's the whole-hog gushers/guilt trips/desperate-negotiations-as-if-with-God convos that drive WAS away. IMHO, anyhow.
Is it possible to be DarkFriendy?
"Show me a completely smooth operation and I'll show you someone who's covering mistakes. Real boats rock." -- Frank Herbert