Geila, I don't even know what to say to your post. While there have been people in my life that I've found annoying I have never wanted any of them dead. And I certainly wouldn't have asked their kid/my spouse "when is your mom going to die already?". And if any hypothetical spouse of mine had asked that of me they would soon not have been my spouse anymore. I'm lucky that my MIL and deceased FIL are/were amazing people, but good god, what would it say to my SO if I told him I wished his parent was dead?
As a pretty hardcore introvert I can kind of understand not sharing the downside to "whatever the problem is" with a lot of people. (Contrasted with sharing the fact that I'm gay. I don't consider that a downside in any way, it's just who I am so I share that freely with whoever if it happens to come up in conversation.)
But when SO had a very serious illness a few years ago, for example, as I struggled with my fears and worries it just didn't occur to me to just put it out there. I reached out to a couple of longterm close friends for support on a daily basis. To the rest of the world I presented as "I"m fine. We're going to get through this." I think part of the reason I did that is that I couldn't handle people offering their concern or whatever and me having to thank them or assure them I was ok. It was easier just having them treat me like a normal person because they had no clue something was wrong. During that time a distant professional acquaintance randomly told me that his wife was going through a similar struggle to SO. I opened up to him about SO and we ended up having a really great conversation about our shared worries and concerns about the future (not identical, his wife is way younger than SO and they have two fairly young kids.) But I couldn't have just posted on linkedin, "by the way, SO is struggling with a potentially fatal illness that the docs can't figure out. If you, or someone you love, is also in this boat, reach out to me..."