From The Movie Snob:

We Don't Live Here Anymore (B). This is a movie about adultery, and not the glamorized kind of adultery you see in movies like Unfaithful. Jack & Terry and Hank & Edith are two married couples and best friends in a New England town where Jack and Hank both teach at the local community college. From the opening scene, it is clear that Jack is powerfully attracted to Edith, played by the always appetizing Naomi Watts, and that his marriage to Terry, played by the amazingly angular Laura Dern, is in trouble. Making matters worse, Hank & Edith have a little girl, and Jack & Terry have a little girl and a little boy. Most of the movie's action, such as it is, consists of brutal fights between Jack and Terry, which struck me as utterly convincing and very painful to watch. None of the characters is particularly appealing, which is probably what inspires my middling grade -- the movie held my interest because it successfully made me wonder what was going to happen next. But I never got past curiosity, or rooted for any particular character or outcome. Except to feel sorry for those poor kids.