I can see why Ann Hathaway got the positive reviews that she did in this. It was a break from previous type casting, and her non verbal acting alone was extremely memorable. Having said that, honestly...? This thing felt as if someone took clip footage of someone's home wedding and spliced in about 10 minutes worth of a well done indy short that you might see at Sundance. The entire thing was in shaky cam. I'm not a big fan of shaky cam, and I really don't feel it made this more realistic.
The slow reveal about the underlying tensions despite the veneer of positive relations when the family originally met are well confirmed. The echoes of a tragic event (not spoiling it) revealed were well choreographed, and you can understand that they have so much footage of the wedding and preparations thereof to help establish emotional ties to the characters as well as hide the building sense of drama in plain sight.
It is also well done in that it is not 'cliche.' The main character does not, for example, relapse as you might expect (that's not a spoiler). People are human.
Having said that, I really still honestly felt this film could have been about half of the length it was. Would that have made it commercially unviable to have a 44 minute film instead of 88 minutes?
Maybe. But it would have been a hell of a lot more watchable. There is a lot that is solid and well done in this film but it still needed a serious edit pass. Particularly in the toast scene where the protagonist gives her awkward speech and then, because we can, we give 3-4 more. Maybe to show that other people went after here? Why did we need to know that?
It was gratuitous and frankly silly. Good movie. Worth watching. On 50% fast forward.