What a terrific essay this is!
Lots of insight, lots of wisdom and a great look at what being a writer is like.
I also loved the way you turned your inability to write an essay into an essay about your inability to write an essay.
That's a real pro move.
One important takeaway of this story for me is that EVERYTHING that happens to a good writer is material.
If we run into a wall on our first try, all that means is that we need to figure out another way in.
By writing about the fact that you couldn't write about your mother's death, you've begun writing about your mother's death.
I know that you will eventually write the essay you originally set out to write, and that'll be a great essay too.