I think it was inappropriate for your therapist to bring up her diagnosis in that way. Self-disclosure on the therapist side should only happen for the benefit of the client. If she brings it up again, I wonder what she would say if you asked her "Why are you telling me that?"

I had one therapist who brought way, way too much of her own personal stuff into my session. Now I'm a little gun shy when they start talking about themselves even a little bit. I have no idea if either of my therapists have any kind of mental health diagnosis, and I'd rather not know. Neither would bring it up on their own. I don't know if they would tell me if I asked. But I'm not going to ask, because I'm selfish in therapy and I don't care. I think if they want to talk about their stuff in therapy then they should be paying me.