BOOK REVIEW / FICTION : Writer’s Doomed Love Affair Wavers Between Myth and Reality : DIANA: The Goddess Who Hunts Alone <i> by Carlos Fuentes</i> ; translated by Alfred MacAdam; Farrar, Straus & Giroux $21, 218 pages

If it were not labeled a novel, “Diana” might be mistaken for a memoir by the celebrated Mexican author, Carlos Fuentes. Real-life luminaries such as Bill Styron and Luis Bunuel show up, and so do such stars as Tina Turner and Clint Eastwood.

So when the narrator, who is also a Mexican novelist named Carlos, confides to us the details, both sexual and spiritual, of his brief love affair with a movie star named Diana Soren, we cannot help but see her as a thinly veiled rendering of Jean Seberg, the doomed American actress who fled to Paris but never escaped the demons that ultimately destroyed her.

Diana Soren, like the real-life Seberg, is married to a French novelist, takes a Black Panther as a lover (and the reputed father of her child), draws the unfriendly attention of the FBI, and finally crashes and burns, a victim of media, politics and pop culture.

“Diana” opens on New Year’s Eve, 1969. Carlos has just turned 40 when he meets--and, he thinks, falls in love with--Diana. He admits that he is in the throes of what he calls a midlife crisis, but he insists on seeing Diana as not only a “film goddess” but an authentic deity, too.

“Nocturnal goddess . . . the huntress . . . virgin followed by a retinue of nymphs but also mother with a thousand breasts,” writes Fuentes. “Diana worshiped at the crossroads of Time Square, Piccadilly, the Champs-Elysees.”

Carlos is attracted to Diana for all the ordinary and tiresome reasons--she is young, beautiful, glamorous and sexually available. When he follows her to the location where she is working on a movie, he recognizes that their couplings are a kind of drug that soothe him and excite him at the same time.

“Let’s kill our tedium with sex, alcohol, gossip, immortality,” Carlos muses out loud, recalling the hottest moments of a love affair on a movie set. “Sex told us we were alive even if the place was dead.”

But the love affair between Carlos and Diana is doomed. Carlos is soon annoyed by her quirks: “Open bathroom doors scare me,” she tells him. He is jealous of her other lovers, including the man who exists only as a mysterious telephone caller and, rather perversely, one of her former co-stars: Clint Eastwood, “an Achilles of leather and stone,” as Carlos describes him.

Eventually, Diana delivers the blow that would be devastating to any philandering middle-aged married man who thinks that bedding a younger woman is a solution to his problems.

“Mister, you’ve had two weeks of pleasure,” she tells him. “When are you planning to give me some?”

Fuentes is plainly fascinated with the interplay between myth and reality, and he manages to elevate the figure of Diana Soren to something both tragic and heroic. So the story of a failed tryst becomes something much grander than it first appears--a celebration of sexual jealousy as an act of “erotic will,” a spurned lover’s elaborate rationale for what went wrong in bed.

“I began to be haunted by the idea that Diana was a work of art that had to be destroyed to be possessed,” declares Carlos. “Jealousy kills love, but it leaves desire intact.”

But Fuentes himself seems to acknowledge what is going on here. He allows Carlos’ estranged wife, who has endured other infidelities before this one, to define exactly what Carlos is seeking in Diana’s arms.

“You don’t respect the women you sleep with,” she says. “You use them as a literary pretext.”

And, in a sense, so it is with Fuentes himself. We are allowed to watch as the flesh-and-blood Diana Soren, like the real-life Jean Seberg, is allowed to meet her own sordid fate, but Diana-the-demigod lives on, a shimmering figure in the overheated imagination of the novelist named Carlos.

“Literature is a wound from which flows the indispensable divorce between words and things,” Fuentes observes early in the novel, thus revealing the novelist’s conceit that lies at the heart of “Diana.” “All our blood can flow out of that hole.”