Mine (which I hope wasn't crossing some line...):
"Hi MC,

I realize the one-sentence e-mail (from yesterday) probably seemed kinda odd--though I did really just want to share that insight. But there's something I wanted to say related to last session, too.

Your "preemptive reassurance" at the end really did help. Not just in what you said, but in how you were talking to me. And there was something else about it, too. It made me realize that the "old MC" (used his first name here, which I don't usually do to his face) is still in there--that maybe that part of you is obscured somewhat by grief and everything you're dealing with--but that really empathic, caring version of you isn't gone.

I'm sorry if it seemed like I expected you to be the exact same person you were before--or at least the exact same therapist. Like you said, of course something like that is going to change you. And I hope you're managing OK. I'm sure that you're just doing the best that you can, including with your patients. So, thanks for still being there, even if it is a little different sometimes.

--LT"