This opening scene finds Dana taking the long way to her supermarket to avoid the school where Jerry teaches, and where he's known to remain long after the last bell on behalf of his students, "correcting papers, offering extra help, and throwing baskets in the gym." One gets the feeling that Jerry's solicitous nature did not extend to his relationship with Dana—a suspicion confirmed later at the Stop & Shop deli counter, where Jerry's ghost berates her for buying mashed potatoes to go with her rotisserie chicken.
The technique employed here is interior monologue, also sometimes referred to as stream-of-consciousness after the term coined by psychologist William James. But while the stream-of-consciousness technique tends to encompass narratives as a whole (such that descriptions, setting, dialogue, and actions are all conveyed, as it were, by the flowing stream), interior monologue functions as a distinct device within a traditional narrative—as in the given scene, where Dana's thoughts enhance the narrative, but don't subsume it.
Compare with this passage from the most famous stream-of-conscious narrative of them all:
... Mulveys was the first when I was in bed that morning and Mrs Rubio brought it in with the coffee she stood there standing when I asked her to hand me and I pointing at them I couldnt think of the word a hairpin to open it with ah horquilla disobliging old thing and it staring her in the face with her switch of false hair on her and vain about her appearance ugly as she was near 80 or a loo her face a mass of wrinkles with all her religion domineering because she never could get over the Atlantic fleet coming in half the ships of the world and the Union Jack flying with all her carabineros because 4 drunken English sailors took all the rock from them and because I didnt run into mass often enough in Santa Maria to please her with her shawl up on her except when there was a marriage on with all her miracles of the saints and her black blessed virgin with the silver dress ...With this sort of stream-of-consciousness, the author relinquishes—or appears to relinquish— control of the narrative to the mind of his protagonist. In fact that "loss of control" is entirely and cunningly contrived to give the appearance of spontaneity and randomness, much as the drips and spatters on a Jackson Pollack appear to be random and spontaneous (they aren't).
With interior monologue the author never quite lets go of the reins. In the given example the narrator (as distinct from the protagonist) remains behind the wheel, as it were, telling us, between forays into his character's thoughts, how, having choked back the bile inspired by a vision of Jerry shooting hoop with his charges, Dana "took a left and another left, heading toward the Stop and Shop." The narrator goes on to explain that in shopping Dana "is all business, plucking apples, bananas, strawberries, and raspberries—expensive, but she deserved them." Note how with that "but she deserved it" we are dunked, however briefly, into the protagonist's subjective stream, back into her interior monologue. That she plucks apples and strawberries is an objective fact; that she deserves them is purely her subjective opinion, a taste of interior monologue.
This subtle mixture of objective authorial narration and a character's subjective perspective goes by its own names. Called close third person by some and free indirect style by others, it lets narrators move seamlessly between objective reporting ("Dana wheeled her cart over to the deli counter") and a character's thoughts ("Oh, mashed potatoes."), to where at times one can barely distinguish the two ("she planned to enjoy these mashed potatoes").
The virtue of this technique (aside from dispensing with all the "she thought"s and "it struck her that"s), is that it flavors the whole narrative with a character's feelings—as a sliced onion, left next to the butter in the refrigerator, flavors the butter with onion. Yet unlike the aggressive stream-of-consciousness technique, it gives authors full control over the degree of objectivity.
In this opening the free direct style is well-employed, though one might quibble that if Dana's brain is indeed "working overtime" to avoid picturing Jerry in his classroom, that hard work hasn't paid off well, as we are treated to the very images she's intent on avoiding. Better perhaps to have her inadvertently drive by the school, having neglected to take an alternative route, and thus the image of Jerry gyrating on the basketball court with his charges will be both better motivated and inadvertent.
It seems to me, too, that if indeed Dana is haunted by Jerry, better use might be made of his specter, who ought to be right there in the driver's seat beside her, telling her to change lanes and use the turning signal and that she almost cut that curb. The supermarket scene likewise feels stingy. Why not have Jerry's take on more than mashed potatoes? Why not see him micro-managing Dana's shopping list? Though he may not be there physically, Jerry is a character in this scene—or should be. Under the influence of Jerry's ghost she might hesitate to drop that quart of mashed potatoes into her cart—and then defy him. Surely that beats telling us that this is what Dana would not have done in the past.
However skillfully or seamlessly rendered, a character's inner thoughts are no substitute for actions.