This reminds me of my latest two poems. The topic is universal, though.

I'd like to start with the ending, as if we contrast this with my "Theodore," then here it speaks to leaving something behind, truly, that it no longer is part of you. Though I guess one could question whether nothingness "is," since it certainly seems to constantly pop up.

But while Theodore was a poem of longing, and there is some longing here, this definitely feels more like a poem of bidding farewell, of letting go. But it is a question of who let go of whom, because it feels more than the speaker letting go of a memory, that of the memory deciding to leave.

A memory, or a person.
Because while it is voiced as if it's a memory, sitting with someone who is dying, truly does fit the beginning. And in that light, the poem is about all that that person was to you, passing through you on their way to becoming energy.
And rather than disappearing from your soul, they tuned like tuning forks, to all that they were for you. And then they were gone, not from your soul where they still are, but from the land of the living, as you watched them go.

"Key-holed view," now that is a phrase that arrests my view. On one hand, it can seem as if it is about someone whose view is narrow, who can only peer at the world, rather than see the big open picture.
On the other hand, it is someone who is seeking to see what is hidden, who tries to see beyond the locked door, who is inquisitive.

It definitely feels like a door, or rather, windows are closing, going from "eyes of smoke dissipated" to the "key-holed view."

And of course, the two can be joined, and also apply as a metaphor to us all - how we try to view the world, we keep trying to make sense of it all, to see life. But what we see, is really quite limited, as if peering through a keyhole.

P.S. I Hope Matilde is fine.