There's a lot to talk about in this book, although the first thing I have to say is that I meant to read this months ago, except I have a policy of always listening to Emma Newman's books because I love the way she reads her own work. So it was a matter of finishing the audiobook rather than simply sitting down and reading.
It was really good. And it was strange and interesting and, in some ways, the plot is the least interesting part of the narrative because Newman sets her reader up immediately to recognize that this is a story about things falling apart. So the anticipation is not in finding out what happens or even in how, but in watching the ramifications and their effects on the main character.
A couple of months ago, I was complaining about a particularly bad case of "anxiety, but not really" in a different book. The main character had some of the hallmarks of anxiety, but it never seemed to get in his way or matter. He had just enough anxiety to (attempt to) make him sympathetic without dealing with the real ramifications of thinking that way. I really hated it. This book is the opposite of that. Newman writes her character's disorder with compassion, letting it be a part of her life and having its severity unfold organically.

Because we're in Ren's head, it takes a while before we know she's not merely nervous, but has a full blown anxiety disorder and even more time after that to recognize her hoarding.

The ending is...frustrating, in the way of such endings, because the story is clearly over and yet I wanted to know what happened next anyway. I wanted all the details Ren couldn't provide. But that's the hallmark of a good book - the sense that if you could just get a little further into it, there's a whole world there for you to learn about.