Samantha — Sam in the summer, when she’s away from her year-round school responsibilities and is instead focusing on her swimming — is part of a tight-knit group of girls called the Crazy 8s. For the most part, the girls are hard to tease apart and delineate as individuals. They’ve been tight for a long time, and they’ve done what seems like everything together.

But this year, after a refreshing, invigorating summer, Samantha is feeling anxious about beginning another year of high school with her best girls. In many ways, they’re not really friends. They’re together because it’s part of their reputation and because it’s been part of the routine since kindergarten. Samantha, though, isn’t all in.

It’s not just that she’s feeling distanced from them. It’s that her mental illness — Obsessive Compulsive Disorder, of the Pure-O variety —  has gotten bad. Really, really bad. She’s unable to remove the distressing thoughts from her mind in a healthy way, even though she’s taking medication for it and seeking regularly weekly therapy with a therapist who she trusts and who cares about her deeply.

Fortunately, on that first day of school, things seem different. Samantha meets Caroline, a girl she’d never noticed before at school. It’s Caroline who introduces Samantha to an underground poetry club at school called Poet’s Corner, which meets in a hidden space at the school. It’s Caroline who helps Samantha to more embrace her “Sam” — the girl she is when she’s swimming in the summer and the girl who is most like who she is. It’s Caroline who helps Sam discover a passion for writing, for performing, and who ultimately introduces her to AJ, a boy who Sam had tormented years earlier with her fellow Crazy 8s. When Sam apologizes and begins to see AJ for more than the guy he used to be, they begin a really powerful, well-developed, and satisfyingly dynamic relationship with one another.

I went into Tamara Ireland Stone’s Every Last Word with some hesitance. I’ve read more than one OCD book in the last few years, and while they’ve all explored the illness in some unique way, I always worry that it’ll be manifested in a way that feels more like a television representation than authentic to the illness. But it was pleasing to see Stone didn’t do this in the least. Sam’s OCD in this book is rendered incredibly, authentically, and might be one of the best mental illness books I’ve ever read.

YA loves mental illness, and this isn’t a bad thing. The problem I’ve found, though, is so many of these books read like check lists in some capacity. You can see the research the author put into the book because the character and his/her behaviors feel like the research itself. She/he does this, then this, then this, and then there’s the diagnosis of the illness.

But Ireland Stone subverts this trap through the research.

Samantha has a type of OCD that is less about the compulsions and more about the obsessive and distressing thoughts. That doesn’t mean, though, she completely lacks any compulsions. She has to do things in threes. She can’t, for example, park her car if the mileage isn’t ending on a multiple of three. But this isn’t about those things; the real misery for Sam is how she cannot stop thinking horrific things. Not only do we see those horrific things, but we experience them along with her. She’s fearful of what will happen in every single act she undertakes, and she tells readers how miserable it is to have these thoughts. She’s anxious all of the time, and while many readers may not understand that anxiety as it creeps in — so many of the things that shouldn’t cause it are — I couldn’t help but completely, utterly relate to Sam in many of these manners. I have anxiety issues, and though it is not to this extreme, I felt those feelings and fears with Sam because I completely empathized and sympathized with her. It’s difficult reading, but it’s a window into a mental illness that’s well-done.

That’s not where it stops though. From here on, you have spoilers, so jump down to the last two paragraphs if you don’t want them (that starts with “The romance”).

One of the things Ireland Stone does is offer a piece of Sam’s illness that isn’t “on the books.” Caroline, the girl she meets and who introduces her to Poet’s Corner and AJ, isn’t real. She’s a figment of Sam’s overactive, illed brain. Sam talks about Caroline at numerous therapy sessions, and through those sessions, we learn what Caroline is to her: she’s a force that pushes Sam outside of her comfort zone. Caroline is the way Sam allows herself to push boundaries, as well as the way Sam is able to overcome her anxiety about doing new and different things, including reading and writing poetry, apologizing to AJ and pursuing a relationship with him, and pushing outside the security and comfort of the Crazy 8s, even though they’ve been her long-time friends.

Caroline’s not being real doesn’t particularly trip up Sam’s therapist. Rather, her therapist talks about how everyone’s brains are really special and unique, and those who struggle with mental illnesses don’t all struggle in the same way. Rather, brains are so interesting that even diagnosable illnesses can take on different forms, different coping mechanisms, and create these rich stories that don’t make sense to anyone. Caroline is part of Sam’s coping, her brain’s means of pushing her forward and through her day-to-day. Ireland Stone’s subversion here — the assurance she offers Sam through the narrative, through Sue and more, the assurance she offers any readers struggling with mental illness — is noteworthy and commendable. We are “off the book” here in terms of what we understand about diseases like OCD and yet, it’s not treated as if it’s a boogeyman or a malfunction. It’s part of a brain that’s firing strangely on a chemical level and…that’s all.

That is a radical, powerful moment.

Therapy and medication in this book are not big deals. Rather, they’re tools in combatting mental illness and becoming a functional, healthy human being. The medication discussion here is about how it can sometimes take work and how sometimes, there is an adjustment period and adjustments necessary to make them work the best way that they can. Ireland renders Sue, Sam’s therapist, as a full and functional human beyond the “role” she plays as a therapist. In fact, the book does a great job depicting all of the major adults in this book; they’re all there, and even if they can’t all be helpful, it’s nice to see them as fully-realized characters, rather than secondary and less important.

The romance in this story is really rewarding, and for many readers, this will be the highlight of the story, not the treatment of mental illness. AJ and Sam do not have an easy romance at all. AJ is really not all-in with Sam, and he doesn’t welcome her immediately. Even after she apologizes for how she used to treat him, AJ is tentative. He doesn’t want to give her all of his trust immediately, and there’s pushing and pulling that’s authentic, challenging, and true to how romantic relationships in teenagers work but that we don’t get to see in fiction quite enough. There are no fireworks here, no quick resolutions. This relationship takes work. It’s earned, not expected.

Every Last Word comes out June 16, so the review is a little early, but it’s a book worth putting on your radar now. Ireland Stone’s writing is fluid and absorbing, and her treatment of such an terrible, painful, and frequently mischaracterized illness is outstanding. Sam’s story is engaging. Readers who like the writing and story telling of Sara Zarr or Siobhan Vivian will find much to enjoy here, and readers who like the romantic arcs of Jenny Han a la her “Summer” series will find that here with AJ and Sam. Highly recommended, with great appeal to those who are curious about mental health, as well as those who may not know they are.

Review copy received from the publisher. We’ll be doing a giveaway later this week of this book, too, courtesy of the publisher.