Berowne's 143

(Also for Three Word Wednesday and ABC Wednesday: "R" is for "The Remembering")

(Strange. The prompt this week, the threat of violence in World War I, the forest seen in the distance, suddenlhree y had me thinking of an entirely different event, an entirely different era. It's a bit of a stretch but it made me want to post my version of a familiar story. Listen, as an old man speaks...)
I know, I know; I heard the news.
She took her own life. It’s just as well; she would have died anyway.
Because truth is, she died before she died. What is it, a creature that still contains the outline of human form but whose sanity is wholly, irretrievably lost?
Her constant babbling about the cause; the mind was broken, shattered.
But that is The Remembering, which is what I try to avoid because it belongs to the dim borderlines of the past; it implicates me in what has been done. Instead, I think of now. I think of my new life.
Yes, it’s a castle. But anyone can take a castle. This is more. It’s a fortress. And a fortress is – what is that word I want? Unassailable? Impregnable? Yes, that’s it! Impregnable! Safe. Secure.
That’s what I thought. That’s what I believed. Until...
The day came that I glanced out toward the horizon, as I do every day. I saw nothing. Nothing different. There are trees out there, not much else - a forest.
Then the Thing happened. The thing happened that could not happen.
In the long twisted history of man, in the millenia since humankind first emerged from that alluvial mud, such a thing had never before taken place.
The forest – began to move.
It moved toward me!
I thought for a while that my mind too was in a state of collapse. Hallucination, illusion, surely that must be it! But my mind was not broken; it was clear. I had thought, I had cerebration, I had reason. I could see and understand what was happening.
Even though it could not be happening.
But the forest kept moving, progressing slowly but inexorably toward me.
However, I was in my impregnable fortress. Safe.
Safe..?

[Forgive Berowne. He tried a little test, to see if somone would "get it." It was described as a version of a familiar story. Here's the question: What story? And here's the answer: "Macbeth"]
(Also submitted to Sunday Scribblings.)