Mental Illness and Other Thoughts (Spoilers)

Just watched this one and came here to see what others made of it.

I was thinking the whole movie might best be seen as a play on shared mental illness.

There was cutting behavior; something crawling under the skin also reminded me of the descent into madness in the movie BUG (2006). When the guy threw the box of paperwork off the stairs and attacked co-workers, and the frenzied drive home; followed by digging up the yard in search of some strange noise- it seemed that mental alienation and disassociation might be what was really going on; the pig farm and thief character might have been mere psychotic episodes or attempts to rationalize bizarre behavior.

There were numerous references to drug taking throughout the film.

Imagine if every time someone cracked up at work; missed a few days and acted strung out on drugs it was really due to thief and sampler characters running around the countryside, destroying the sanity of otherwise normal people!

Also it occurred to me when the transfer operation was performed between Kris and the pig-was this an echo of the New Testament story of the possessed person who had their demons cast into a herd of pigs?

The fact that the two leads tend to reinforce each other's alienation from society reminds me of certain unhealthy alliances made between, for example, again, drug abusers.

I'm mostly seeing elaborate explanations of the nuances of the thief and sampler characters here on this board, so I assume most people are taking their existence as an established fact within the movie's created world. Unless the last scene is intended as fantasy, the newly liberated former victims of the thief are now running the pig farm. Speaking of pigs-was there also an allusion intended to "Animal Farm"? The control aspect of the thief's treatments could be seen as a critique of conforming to orders.