How can I help you? I'm a female doctor (psychologist).
Hello again -
I'm sorry that Dr. Linda is unavailable tonight. However, I'm more than happy to speak to you again. When it comes to talking to your friend about your preference, is there any reason to think that he would find this out on his own? (e.g. does he go to an athletic club with you, etc)? If there is no reason to think that he would find out naturally, then there isn't a need to tell him - unless you want to.
If you're very concerned about your family members because you live with them, you can choose to tell them, if you wish. But - again - there is no need to do so, unless you want to. It's not something that is routinely discussed (one's choice or preference for undergarments), so I don't think it's far-fetched to keep that to yourself.
It's not something for you to be ashamed of, but it's none of anyone else's business either, unless you choose to divulge it.
It might be best to follow up with Dr. Linda, as she seems to be your primary contact with this. While I enjoy speaking to you, it's best to keep the same expert engaged because they know the history of the problem. Why don't we wait and see if Dr. Linda is available tomorrow. If not, feel free to send me a message and we can chat, okay?
Thank you and take care