It took me soo long to finish the end of the book - couldn't read for tears heh

>Part of me is just in denial that Dumbledore could have been so very wrong about somebody's loyalties<

Yep, yesh and yeah! heh dumbledore can't be wrong or the sky will fall and the world as I know it will end ;)
And if snape is evil to the point of killing dumbledore - no matter what his darkness says he'd of popped harry there and then (I would have)