A classic
I've seen this a few times and I have to say what a great film it is. Maybe it was too mature, too adult, at the time for audiences not used to this.
What I mean is it shows the usual Hollywood romance stuff, but it goes into time and has these scenes frankly discussing sex in marriage and adultry and how the romance went downhill and why. A romanic story for mature adults. I say mature because they understand what's going on and its not a bed of roses.
The movie yanks the rose colored glasses off the audience and makes them see reality inbetween the romance.