Hi Jane
I have had similar conversations with my sisters. I sent them an email explaining that I was communicating this way because I was having a hard time putting my thoughts together while we talked. I would often hang up feeling beat up. That wasn't their intention but none the less.

I explained to them that while I appreciated their concern and wanted their support, these were the choices I made and I did not want them questioning them. I explained that what I needed from them was their patience, love and to sit with me, listen to me when I needed to talk.

I didn't say this to be mean, but we had reached a point you seem to be with your sister. They weren't happy with it but they respected it. I didn't say, but I implied that it was either this or I wouldn't be able to continue to share with them. I have enough to deal with.

They are well intentioned and I know they love me, but they have different ideas of how my illness should be treated. In the end, they are not the ones to have to go through it, and thankfully, they have no idea what its like.

I wish you luck with your sister.