What a brilliant fic, it's simply beautiful with its objective ugliness.
You've captured Marietta's torment, confusion and misery perfectly; it's an excellent characterization. Such a public punishment always seemed, to me, to be too ruthless and vicious, but this poignant story with its fluid flow stirred a great deal of outrage on Marietta's behalf. My Mama Bear fur was quite ruffled. ;)
That the relationship with Pansy is both disparaging and healing seems so appropriate and very believable. The trauma and invisible scars Marietta has suffered from such extreme ostracism would make her 'better than nothing' relationship with Pansy seem quite appealing and acceptable. That it appears that she and Pansy may help each other grow into a more positive place is nice touch.
As I wrote above, this is brilliant. It's also analytical, perceptive and candid, a fabulous contribution!