Before I address the questions that you posed, I'm going to mention a couple of grammar/typo issues I noted down while reading. I think "more real" is a more accepted way of saying "realer." "Chocking" should be "choking." In the italicized line about the light on earth, you should use "is" instead of "are" (because light is, not light are).
I can understand why you have had some readers remark that this is a nice piece in terms of imagery but doesn't seem all that substantial (I guess in terms of plot?). I suppose I have to agree, in general. I think the chapter overall has a very nice flow to it. As you said, it is rather floaty. It is rhythmic. The beauty of the flow almost overpowers the extreme suffering the character appears to be undergoing.
However, it is a bit difficult to tell what is happening or why. There is a lot of pretty description of a character suffering extremely, but we don't really gain a very good understanding for just why she feels so darn sorry for herself and why things are so extreme. It almost seems like she is suffering for the sake of suffering.
Then again, I could have missed the point. :P I've been known to do that. I actually like that you have a story here that is approaching a more proper short story format (short story as I understood the term in literature class, not as HPFF defines it by word count). This story did remind me a lot of short stories read for class, and generally to answer questions about those, I have to think about it longer than I have for your story. That said, I do feel like a lot of short stories I read in school packed a little bigger punch at the end, even if it took a while for me to understand. I do think this story suffers from a bit too much ambiguity, or not enough backstory (maybe I would feel differently if I had read the other pieces you mentioned in your author's note).
Now I'm going to finally try to answer your questions. What do I think happened at the end? I think Death Eaters came and took Florence. I also got the impression that she wished for them to come for her.
I do feel some sympathy for her, because it is difficult not to feel some sympathy for someone who seems to be in so much pain. However, I don't feel that I care a great deal for how she got there. I would like some more details to make me feel more invested in her story, because as it is, her pain feels rather abstract to me, and difficult to relate to or understand. She obviously feels some great guilt, but I need some more hints (or leading questions, haha). That last line also leads into my answer about why I think she did what she did: out of guilt, I suppose.
For all my criticism, I did find this a pleasing story to read (despite all the suffering!). As I said before, it has a pleasing, rhythmic flow, and the imagery is indeed nice. I do think it is difficult for the average reader to make the connections you wish, though.
Author's Response: Thank you for your honesty! It was definitely something i was worried about if anyone would actually 'get' this piece because although the connects are glaringly obvious to my eyes, it probably only because i know the whole story and i know what each sentence or hint is pointing too. It seems like those connections however were only happening in my mind. :/ .
So, in leu of that, i've edited it and added on a few hundred words trying to give that backstory and make some of the connections clearer. It's still a bit ambiguous but i'm hoping with what i've added it grounds the story a bit more and makes it more concrete.
I know i have the tendency, especially when i write third person to have that weird floaty style of writing and i'm not sure how i feel about your comments about how it's just so pretty, especially with the amount of suffering going on. I hope that it isn't distracting or purple prose as that would be a nightmare.
I suppose the whole idea behind this was her guilt for sacrificing the stranger with the red lips in hopes that it would bring back her sister. I don't think i made that story line clear enough or why she thought that was possible. Which, in my head, there is this myth that says you can replace one for another. In the story i'm writing solely on her there will be a lot of that back info about that myth (one i've made up) and how Florence goes through this whole journey trying to bring back her sister and it plays with some actual theories of time (not actually time-travel though). Anyway, without that story I realize this scene probably makes no sense so i've tried to clear it up a bit in the edits i've made. Hopefully it's not quite as ambiguous.
Thanks again for your opinion and taking the time to read this! I really appreciate your input :D