Hello StatelyHomers. I've been following this thread for a while now and have name changed for this, incase I'm outed elsewhere. I'm afraid it's a bit long, but wanted to give the (current) story straight up.
My mother is toxic and she is definitely narcissistic, although not as badly as she could be, so I've found out. She was abusive when I was younger (again, could have been worse, but was bad enough for me) and I have previously had and am currently having therapy for it (since the birth of DS I can barely look at her, I'm so disgusted with her).
So, for the past 17 years, since I was 17, she has been talking about her death. It started with the type of coffin she wanted, then progressed to me handstitching a patchwork quilt with her, a nice 'mother-daughter activity'..for her shroud!! It progressed onto sorting out the paperwork for after her death - will, living will, listing bank accounts etc. Now, I know it's INCREDIBLY responsible to do that, to save others (me and DB) from a potential nightmare. The thing is that I have never, ever been active in these discussions. At the beginning, when I was still living at home, I'd duck and dive the discussions. Later I said, politely and gently, that I didn't want to discuss these things, and following that being ignored, I bluntly said I wasn't interested, she should sort it out with her lawyer. At all stages of the paperwork discussions (a good 10 years) I have said I was thankful for her doing it, alongside, later saying I didn't want to hear it any more.
So, over the past 4 years, when I've been extremely clear and sometimes rather blunt about the fact that I do not want to hear any more talk about this, she has basically ignored me. We live in different countries (thank goodness 
) and I saw her in the autumn. She said, "I know you don't like talking about this, but.." and just continued on about her will and the rest. I didn't feel like an argument, the subsequent sulk and pregnant pause where I'm supposed to apologise (and never do), so said nothing (and I mean not a word), looked disinterested and didn't really listen to what she said.
She came to ours for Christmas and stayed a few extra days to look after our cat while we were away. I KNEW she would be up to something, but I couldn't figure out what. I came home today to a note on my dining table. It turns out, that "..because she has no partner, or close family.." (the 'partner' line has been on repeat since I was about 12: poor her, she's all alone..) she had left a copy of all the documents with me, and sending a copy of them to my brother.
I am FURIOUS. I feel completely disrespected. She knows I don't want them, she has an executor (I previously declined to do it, in part because I didn't want these documents ahead of time - which I'd said, very clearly) and I feel she has been absolutely underhand in leaving them.
Of course, my thoughts about this (according to her I'm too repressed, death is a part of life, we should be more open about it), are completely inconsequential to her. I can only liken this to a semi-bridezilla planning her wedding and ignoring the pleas of the people around her, because it's 'her day'.
I have no idea what to do though. I want to email her and tell her a whole load of things I can't retract later, but will undoubtedly elicit a 'poor me, you just attack me' response and DH thinks I should just say nothing. I also thought about sending her back the documents with a note along the lines of "We seem to have misunderstood each other, I do not want these documents, so am returning them."
Is there any point though?
I'm also very near going NC with her, but know I won't just yet. I have been cutting down contact over a long time and have decided to further restrict it - including to my DS, which I've been trying hard not to do - because it's not good for my health.
Oh, and I should add: she has never had a life threatening illness, or the possibility of one. This is coming from someone who is and has been perfectly healthy (well, physically!!). If she'd had a serious illness, I would have been much more sympathetic and actively helped - at least for the first few years!