La Peau Verte by Caitlin R. Kiernan, appears in the collection Horror: The Best of The Year, 2006 Edition (edited by John Betancourt and Sean Wallace).
Plot synopsis: A down-on-her-luck artist and model finds herself taking an unusual modeling job for a very unusual client, and ends up losing herself in the part.
The story opens with the main character, Hannah, observing in a mirror her transformation--through cosmetics, paint and prosthetics--into the Green Fairy. The description is quite detailed, and the character finds it very hard to recognize herself. It's all part of a role-playing job that the down-on-her-luck artist has taken to pay the bills.
The story then leaps back to a series of character interactions between Hannah, her best friend Peter, and her psychologist. It is through Peter that Hannah gets the job role-playing the Green Fairy (and her introduction to our friend, La Fee Verte), while it is through her interaction with her psychologist that we learn of the traumatic death of Hannah's sister, and Hannah's brush with the Otherworld.
And, of course, there is the character's introduction to absinthe (which has it's own chapter in the story):
There are references to Absinthe: History in a Bottle and Artists and Absinthe, with some detail given to Albert Maignan's The Green Muse:
I wouldn't classify this as a horror story, but as magical realism/fantasy; true, the scene by the well could be called horrifying, and the ending definitely invokes the Weird, but the story doesn't reach out and slap the reader like horror should, the way that Laird Barron's Probiscis does. Still, that's just my opinion, and I do consider this an excellent story.
Those interested in Ms. Kiernan's work might wish to visit her webpage or her journal.
"I am a drinker with writing problems." ~Brendan Behan