Not another one please (SPOILERS)

I am so tired of films that expect their audience to make up their own ideas as to what it's about as they go along.
We are not offered anything more than vague hints as to why Lily is as promiscuous as she is - the tired old "abuse at home" carrot is dangled but never gone into to let us know if that was indeed the case, leaving people with lurid imaginations to make up all manner of silly scenarios.
I don't believe Lily was abused by anyone - including her teacher - she was simply a promiscuous teenager who wanted to get away from the restrictions of her parents. Tommy was simply a child who liked to walk at night - neither were abused by their parents. Lily simply decided to follow him one night and keep on going when she was offered a lift. The film expects us to believe that she left her little brother on his own in the middle of nowhere in the small hours with no concern for his welfare. I don't buy that. I also don't buy why Tommy became speechless for no apparent reason - had he been beaten up, raped, and left for dead, then yes, good reasons, but simply because his sister got in a car?
I also see no reason for the mother to wander into town naked - just another ploy to titillate those who like to see a naked human being.
I don't understand why the husband was so cold towards her - no reason was offered - but at least it made her desperate attempts to find some kind of loving understandable.
Why they bothered at all with the Australian folklore myth I have no idea - it wasn't applicable to the situation and led nowhere.
Children disappear - the land takes them? really?
And finally - the non resolution ending - how fashionable and how lazy and if you don't like it you have no imagination etc etc. yawn.
A film that tried to be mystical and failed miserably.