Added 4/15/12.
I haven't read this novel but I did watch the film, which I streamed from Netflix. The film was adapted from: Passionate Friends (first published in 1913) by H.G. Wells. I gave the film 4 Netflix stars out of 5.
FILM: "The Passionate Friends" (1949)
Cast: Ann Todd, Claude Rains, Trevor Howard

IMDb description:
"The Passionate Friends were in love when young, but separated, and she married an older man. Then Mary Justin meets Steven Stratton again and they have one last fling together in the Alps."
FROM: http://www.imdb.com/title/tt0041735/
[IMDb lists the movie as "One Woman's Story"; "The Passionate Friends" was the original title.]

Netflix description:
"While staying in the Swiss Alps, Mary finds herself torn between the convenience and financial comfort of her marriage to Claude, who is much older, and the passion of her old flame, Steven."
FROM: http://movies.netflix.com/Movie/The_P...

The following dialogue from the film was impressive. Mary's husband (powerfully played by Claude Rains) says to Mary:
"You gave me love and kindness and loyalty but it was the love you'd give a dog and the kindness you'd give a beggar, and the loyalty of a bad servant."

Below are some interesting comments from Librarything.com about the novel:
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"The Passionate Friends (1913) is one of three books Wells wrote about social justice and feminism, along with Marriage (1912) and The Wife of Sir Isaac Harman (1914)."

"The Passionate Friends explores the relationship between Stephen and Mary. Mary's desire for independence leads her to reject marrying Stephen, since he's below her in stature. She can't see who [how?] she could have the freedom she craves if she were to become a housewife ... Mary marries a rather bland but wealthy man, who is willing to cede her the freedom she craves. ...when Mary and Stephen are discovered in an affair her huband revokes her privileges."
...
"Stephen, like many of Wells' characters, is deeply flawed in his blindness to her motivations. Though he is the narrator (the novel is written as a memoir for Stephen's son to read and learn from), it is obvious he is not a reliable narrator when it comes to Mary."
FROM: http://www.librarything.com/work/110493
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NOTE: The movie presents the wife as the narrator, not Stephen.

Some reviews of the movie can be found at:
http://www.eyeforfilm.co.uk/reviews.p...
http://homepages.sover.net/~ozus/pass...