OMG, you could be me writing this, except that I don't live with my mom. (I don't think I could have handled it, frankly) It drove me bonkers that my mom seemed to need to broadcast the news of my illness and all the associated details far and wide. When I asked her to tone it down, she said she needed to talk to people, it helped her deal with it, and then tried to make me feel guilty about not wanting the world to know my private information so that they could pray for me and give me sympathy. My full name was published in church bulletins in my old hometown and all over the area, by people I didn't even know. Maybe I should have felt loved and cared for, but honestly, I felt like my privacy had been violated, and like the information that was being passed around was totally out of my control, and it was a feeling that made me really uncomfortable. I wish I had thought to encourage her to see a counselor, but honestly, I don't think it would have helped. Even now, she'll say, dramatically, "we almost lost you!" when people are around, just to get a reaction. It makes me cringe, and it makes me furious. She knows this, and still it goes on. She's in her 80s, what can I say? She's never going to change.
This is hard enough to go through without the details of your illness and treatment being fodder for gossip. I'm sorry I don't have a solution, only sympathy, and plenty of that. Stay strong, you'll get through this. Best wishes for successful treatment, a full recovery, and plenty more years of being annoyed with your mother.