Fans of the movie, please help me understand...

I really liked the last half hour of the movie--it was moody and atmospheric--but there were many stumbling blocks in the first hour or so that left me scratching my head. Mostly this has to do with the acting and writing.

Are we supposed to identify with Donald Sutherland and Julie Christie (their characters, I mean) as actual people? Because they behave really oddly. Their performances are quite bizarre, over the top, and frankly laughable at times, particularly Sutherland's. I can't figure out if director Roeg just didn't have a handle on the tone he wanted to strike, or if he was intentionally trying to maintain a surreal atmosphere by having Sutherland and Christie act like aliens or weird robots.

For one, I never believed for a second that they were a couple recuperating from the loss of a child. In one scene, Christie even teases Sutherland, saying something along the lines of, "You're the one who told her to go play outside" on the day of her drowning. First of all, only a sociopath would imply that her spouse was responsible for their daughter's death IN JEST. I could see a comment like that coming out in the heat of anger, as parents tend to blame one another over a child's death, but never would one joke about it. And Sutherland's reaction is little more than MILD IRRITATION when he should be shocked, disgusted, angry, and guilty. No real people on Earth would behave in this way. Was it bad screenwriting, or a deliberate attempt to establish that nothing in this movie should be taken as an illustration of any dimension of known reality, even an emotional one?

And the whole subplot about Sutherland contacting the police because he THOUGHT he saw his wife on a gondola was baffling. I suppose they'd been having a strange trip, but not so strange that he wouldn't just shrug it off and say, "That was weird. That lady looked a lot like my wife. Oh well." If it was meant to imply that Sutherland was losing his grip, it certainly didn't feel earned. It was too big a leap to make the assumption that his wife had been kidnapped en route to the airport and taken hostage by two elderly murderesses, one of them blind, who would then flaunt their potential victim throughout the entire city for no good reason.

Really didn't make a lot of sense to me. But if that was intentional, then to what purpose? I'd like to get another point of view on all this.

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"People either loved us or they hated us...or they thought we were okay."