Seventh Heaven seems to be a "snapshot" of a married relationship that has reached a development stage that neither husband nor wife fully understands. Married for awhile, a son of 6 or 7, a nanny, a nice apartment; he's a surgeon and she's a lawyer/notaire, no apparent money problems. To my mind, what's occurring is partly stagnation and partly depression. There are at least two key factors: 1) The wife is experiencing largely psychosomatic fainting spells, often related to her low-level but historic kleptomania, and 2) The husband is not exactly losing interest but confused over her malady. She winds up seeing a man she literally runs into, who turns out to be a hypnotist; a result is both apparent cessation of her thieving as well as the achievement of the ability to experience orgasm, apparently for the first time in her life. Up until that point in their sex life, the husband has satisfied himself as the wife lies quietly, telling him "not to worry, I just don't get there." Then in her "new life" they're making love and she has an orgasm that she obviously enjoys and in which she wants to include him, but it scares him to death and affects both his desire and performance -- perhaps not untypically for many men. In the end, after much to-ing and fro-ing, they begin to see the changes as being positive; he through conversation with both a fellow doc at his hospital and with another hypnotist that he is unable to relate to. The resolution phase is, to me, fraught with a lot of significant messages that are both non-verbal and hard to "catch" as the movie moves on, but the denouement seems to click. I want to say I wish the film had been more explicit, but that's probably exactly the reason it's so good. It's worth a shot.
