Sam Worthington and Keira Knightley?

Yes, they were slightly akward, but i did see them caring about one another.
I mean they are passed the hummingbirds, being totally in love phase and are having a long term relationship. The guy really plays well the average upper middle class successful kind of guy Keira could be with. I think there has to be a contrast with the french guy, and that is intentionally so. That contrast is what makes this movie work and gives things to think about.

True. I just made a post on the same. She was better with Alex, more in love with Alex.

I think it only seemed slightly awkward just because that's how the movie starts. It got rolling quickly with her showing her insecurity, but I think the awkwardness was meant by the director to give you a feel for how their marriagewas. And the director drops hints with lines like "did we get married to early" and the fact that we learn that she never told Michael about Alex, which gives us good insight into why she's insecure.