I would report him. Whether he meant to reveal your identity or not, he obviously did directly or indirectly or someone would not have approached you. If you feel like he was a good therapist and you feel bad doing so, just think of how he is talking to you now. If you do write him, I would mention that it's pretty pathetic that his own life is so uninteresting, that he has to resort to telling stories of someone else's life. I just wrote a post on how i don't trust mental health professionals and it is for reasons like this. I saw another story online where the poor person was emailed by mistake an email their therapist meant to send to their p-doc that had some negative remarks about them. All the same, I am really sorry this happened to you.