Question about The Descent (spoiler alert!)

SPOILER WARNING! If you haven't seen it ---> don't read!

To me this was a top horror flick. Nothing more.

To my Mum and my brother it was a WHOLE lot more.
They SWEAR it was all her! The Sara Character hallucinated the creepers and she actually killed all the women.

They say that the ending is that she climbs out of the cave in the end, and the hallucination continues as her being back in the cave seeing her daughter. While she is actually sitting in the car.

They say it was all set up coz she didn't take her pills, after she has the dream of the pole thru the head. Hence SHE hallucinated the creepers and she infact killed all her friends.

I have looked and looked and found this theory no-where else. For me that would have made the film even better, but it would have been made different, more just from her perspective. I found the synopsis for the sequel and showed Mum and she refuses to believe it was "just a horror flick"

I would love to hear what others think of Mum & My brothers take on the flick.

__________________
The Furry Crew
"He wasn't JUST a horse.... He was the BEST!"

I have never heard this idea before

__________________

~In the event of a Zombie Uprising, remember to sever the head or destroy the brain!~

No spoiler warning?

Sorry, fixed.

I rephrased the thread title, too, as the question itself can be a bit revealing.