I have a vague recollection of my therapist telling me about a time when she did talk about me with another client. But it was something pretty innocuous, related to my process of applying for grad school, I think.
She's also brought up other clients, but very, very rarely. Sometimes I'M tempted to bring up other clients, both in the general sense, and specifically about this one client whom I kept running to into her waiting area. When I've asked, she's told me a little bit about her other clients - like how many she sees each week, the fact that other clients email her, that kind of thing. Nothing specific, though.
I have issues too with thinking about my T having other clients. And with having children!