I wondered if any one else experienced this- I don't know if mine is the same. It doesn't sound as frightening/persistent as yours- I'm so sorry- your experience sounds terrifying.
I do have this weird thing though- when I wake up that my mind will turn I guess shapes in the room into things and for a few terrifying moments- I do seem to see things. They've been all sorts- figures, fierce dogs, a hole in the wall with water gushing out. Just really weird but usually scary stuff. It's happening more as I get older. Is yours similar to that?
It does feel like I'm awake with my eyes open when I see stuff but it is literally when I've just woken up. Guess it's that cross- over between dreaming and awake but yeah, it's scary and yours sounds even worse