In my oppinion, this does put you in a very hard position, and is something I would not apreciate, having to help my therapist with anything! I had a t in the past who disclosed way too much about her life and family issues in my sessions, and it ended up reinacting the role I had in my family of listener and someone to be there for others, rather than it being my therapy!
If he does this again, I'd kindly tell him to seek medical advice elsewhere. Sorry this happened.