The very fine An Unmarried Woman (1978), by Paul Mazursky, has aged quite well and makes a 21st century film about marriage such as Blue Valentine look lousy by comparison.
This is the one about Erica (Jill Clayburgh), a smart New Yorker who becomes “unmarried” via her husband leaving her for a younger woman. It hits Erica hard, but the film slowly underscores there is still living—and changing—to be done. And, frankly, it suggests there is much to be said for bourgeois living even when marital betrayal has occurred. Still, I agree with John Simon that the second-hour chunk of the movie that features the Alan Bates character is “too precipitately idyllic by half.”
Jill Clayburgh is all T-shirt, legs and breasts in Woman. (Well, not all the time.) Moreover she understands Erica, and her acting is deep and exploratory. Mazursky understands her too: He wrote as well as filmed the mildly ambitious screenplay.
The movie co-stars not only Bates but also Michael Murphy and Lisa Lucas—all good.