It sounds like someone (a moderator of the other site, maybe after a PM by you?) should suggest to this lady that she starts her own support thread. I don't think she means to, but it looks like she is hijacking your thread.
I actually am a moderator on the site. I decided to let it go after reading opinions on here, as it really put it in perspective for me that I probably took it a bit too personally (even if she really was hijacking) because of my own grief. Even though it happened months upon months ago, I'm working on a sticky for the site titled "The Etiquette of Support." Yes, I'm using tips I've learned here.
The site is based on support and help for various issues, so of course the members go there when something happens because it's a place where they can talk about it. More often than not though, people do put their feet in their mouths and/or hijack threads (sometimes unintentionally, sometimes intentionally). I think a thread like that, using things I've learned from this site, will definitely help there.
A brief, intelligent, sympathetic discussion of this issue by "Ask a Mortician" on Youtube - - it really does help.
That video is very good. Thank you for posting it! Maybe that's something I should include in the sticky I'm creating for the other site that I'm a member of.