How sad is this?

It was OK. I don't see why everyone loves it so much. It wasn't very smart or deep or well-directed.

The story-telling is good with flashbacks.The film is both funny and heartbreaking. You smile in a scene and get a soulcrushing revelation in the next.

It's funny, it's tense, it features two great performances from two actors and the director expertly creates a web of odd tension where you actually don't know what is happening for the majority of the run time.