Under the Skin (1997)

Although married and pregnant Rose has always been Mother's favorite, it is younger sister Iris whose life is shaken up by Mother's death. Suffocating, Iris spirals out of control and copes by losing herself in sexual oblivion. She leaves her steady, Gary, for a steady stream of one night stands in the arms of mysterious strangers, alienating Gary, Rose, her friends, and her employers in the process. Will this go on until she loses everything that is meaningful to her?