The novel is never about anything but the obsession that follows this encounter. We don't learn what kind of job the woman has or why the man had to go there, though we suspect it's a legal proceeding of some kind and he's on the wrong side of it.
We never even learn her name, or his. We just get pulled and bumped along behind our heroine as she plunges down a rabbit hole, and things with her new lover grow ever more twisted. Over the course of a slim 200 pages or so the guy steals from her, takes her car for several days at a time, abandons her in strange places, and comes and goes from her house as he pleases, sometimes returning with friends who use the house for a party. He hurts and humiliates, even tortures her, and the worse it gets, the more devoted she feels.
At this point you might be imagining the novel as a titillating-yet-cautionary, girls-be-careful kind of story, something like a made-for-TV movie. It's not. The sex isn't very sexy - it's more worrying than anything - and while the relationship the reader forms with the woman is one of intense identification, it isn't girlfriendy. We're right there with her, that's all, breathing the fusty air of her claustrophobic obsession, and she's really only relatable because her creator has such keen eye for detail. The typical reader hasn't gone through the pain that produced Sylvia Plath's Ariel poems, but everyone can feel the heat from the fire that forged them.
True Things moves on a swift current of short, hard sentences, which in turn are arranged into the brief chapters of a conceit-structure that could have been corny but is tidy and effective: the first-person "true things" of the title. "I talk to the animals," one chapter is called. "I feel empty sometimes" is another. She makes these bald statements about herself, chronicling her own undoing as though she were watching herself from the outside. In fact, that's sometimes precisely what she does:
