Scar Marks and blood on barbed wire

I've seen this movie several times. I think its done well and the acting is great. Excellent Halloween choice for appropriate audiences.

However, during the course of the film, though it provides plausible reasoning for mental illness, the supernatural occurrences shown seem to lead toward a message of a demonic presence. The ending goes further and states her death as an important spiritual event to some.

That being said, the first thing the film shows is blood on the barbed wire fence. This clearly points to the fact that she wandered outside her room and grabbed the barbed wire causing self-inflicted wounds. This was argued as a point of proof by the prosecution.

So what was the film saying? Make up your own mind? I don't think so. To me its pretty clear it infers there are dark supernatural forces at work in the world.

So what's up with the barbed wire?


Does anyone have any thoughts about this?