There's a serious polarity in the reviews for this film,and I'm not surprised. If you've ever suffered depression this bleak movie will hit hard, and you'll pick up on all of the subtle messages it sends out. It's done so well it can't be anything other than achingly familiar. The despondency, and the frustration the sufferer feels at their own despondency, in particular, is well conveyed.
Unfortunately I think a large chunk of the people who've seen this film (and there aren't many who have, sadly) went to it expecting a slightly arty apocalypse movie. It's not a smarter Deep Impact. The (blue) planet Melancholia is just a metaphor for depression. Unrelenting and irresistible, Melancholia has the main character in its thrall.
For those who don't "get" this movie, no it's not a pretentious, pseudo intellectual flick. Rather it's a well crafted take on the fine detail of a subject matter that you have been fortunate enough to not have had to understand. Long may that be the case.