I'm going to give the stuff I thought may be problematic in this piece first, than the stuff I thought worked well. This way you'll at least have to skim the "bad" stuff. :)
The first section has a very nice 'dictionary' feeling to it, as though a neutral object, (the dictionary) has been cracked open to reveal all of this emotion. It helps to convey the idea of seething, hidden passions. The first section, however, is the only one in the piece that opens in like that and I think that it would set a nice tone, (that of unspoken, hidden desires) if every section opened like that.
Also, I can see the energy in the last section of the piece but there are some parts that confused me;
"she says “I hope this kills me.”" - The acid or the not eating? Was it something else?
"The bite marks on her finger a pale shade of red, to match the remains of disorder" - What disorder? A spiritual, emotional, or physical one? One that exists in her, on her, or around her?
"She wants to tell him that she is an ellipsis, and will expand past her own skin and bone, and the stigma of every unholy and medical characteristic she has become" - This just confused me. Is the narrator trying to tell us that (s)he expands like an ellipsis, or that (s)he has an orbit like an ellipsis? Do ellipsis expand?
There are a few other aspects here that I was snagged on as well, although they have no specific textual reference, they are just thematic elements that I feel deserve addressing.
This piece uses the word 'red' often, which I understand is integral to the piece. However, I feel the proximity of one 'red' to another is often too close. I think a few synonyms would be nice in this piece.
"Pertaining to the color of her cheeks when she folded her hands silently across her chest and muted words that she feared she would never have the courage to say"
Very nice. The image of red here conveys some sort of shame, embarrassment, or frustration, (maybe all three) and we can really get a solid image of what's going on and how the narrator feels. Powerful for such economy.
"The passion and fury within the chaos of her core illuminated the entire city red"
Excellent turn of phrase. I really get the vision of power contained inside the narrator, but unchecked and unleashed. The suggestion of illuminating the city red also gives a very subtle impression of how that energy may be being released.
"When the doctors asked her why she was destroying herself she told them it was to keep from feeling pain."
The dead feel no pain, and sometimes it seems like it's worth it. I got a strong impression of the narrators agony and confusion here. Another interpretation may be that causing oneself pain numbs our narrator to the everyday agony of living. Sort of a desensitization self-therapy session. Either way, some good emotion packed into that sentance.
Really, there are more phrases and language nuances than I can go over inside any reasonable amount of time.
To wrap this all together, I think the first two sections are potent and tightly expressed. The third is where this piece starts to loosen up. However, the energy and solid use of language persist throughout the piece and I took a lot of it away with me. All the images and emotions here are delivered directly to the reader in small packages. Well done. :)