I have exactly the same issues. When I visit my GP, on his computer screen, there is the patients significant history, giving a list of absolutely everything. What really gets me is a part of it that says, "1960's sexual abuse". Of course, when I had an appointment with the no-smoking nurse, she could clearly see this on my file and it made me feel very uncomfortable. I've already had a dispute about how appropriate it is to know such a personal thing that took place in the 60's, but the GP dug his heals in. I could have taken it further but cannot be bothered. This is the main reason why I will not have therapy via the CMHT; the confidentiality is within that team and not with any individual worker
People find depression really difficult to understand. For some reason, it is always our nearest and dearest who have the biggest problem understanding. Have you tried getting your wife a pamphlet about depression? I think there are even support groups for family members. I wouldn't like to live with anyone during my depression. Apart from the potential of being horrible to them, having to consider their feelings must be an additional pressure.
I hope you can persuade the Therapist to be a little more sparse with the information. Good luck
