If I had received that reply, I would also be feeling scolded and chastised.

To be fair, your tone at the start of your email was kind of salty, but I think you turned it around and explained well that you wanted his help in figuring out where this was coming from. I don't think he addressed that well at all. When he says that he knows you're going to take his response as cold and hostile, that's when he should have stopped writing and suggested talking about this in session.