Seeing that so many people have gone out of their way to denigrate Butterfly Kiss, I feel constrained to weigh in on its virtues.
It is not a Hollywood entertainment, nor is it a Jane Austen prestige picture, or a politely naughty comedy for the art house crowd. It's a movie for people who are willing to risk a certain amount of emotional discomfort to gain the benefits of experiencing the world through unaccustomed perspectives. It's for those who want to learn about human beings on the margins of society, the forgotten, the pathological, the lost.
It's the sort of film that can't be appreciated without a high tolerance for unsympathetic protagonists, unreliable narrators, unintelligible motivations, and morally ambiguous conclusions.
In short, Butterfly Kiss demands an intellectual curiosity and nimbleness of mind that's not always characteristic of American audiences.
This is not to argue that it's necessarily a good film, or successful at achieving its ambitions. More than once, while watching it, I found myself wondering how much relation to real people this story might actually have. Unlike Monster, with which it has obvious parallels, Butterfly Kiss doesn't appear to be based on factual events.
The film's ability to cause me to "suspend disbelief" suffered from a touch too much Grand Guignol excess and, perhaps more damningly, writerly artifice. (For no clear reason, the protagonists are named "You"(Eunice) & "Me" (Miriam).)
But the characters kept on surprising me, which indicates, if nothing else, that there's something vital and alive about this story. By the end, I was moved to pity for these two deeply damaged women, and, perhaps more importantly, I was moved to compassion.
For that, I'd sit through an unpleasant movie any day of the week.