It's a slow, depressing movie. Well made, thoughtfully scripted, sad film.
Although Olivia Coleman's acting is great, I really didn't like her character. And it's hard to like a film when you don't like the lead character. She struck me as selfish, uncaring, cold and irresponsible, at least in her younger years.
A lot of talented elements like great acting, location, and a tangible tension in the directing sadly mounted up to very little. The ending was a kind of sad, pointless moment in time which didn't really mount to much. What's the director trying to say? It's ok to leave your kids for 3 years, return, and everything will be fine? I don't get the messaging of this film. Waste of time.