JEANETTE WINTERSON'S MEMOIR REVISITS the people and events familiar from her first and most famous work, the semi-autobiographical novel Oranges Are Not the Only Fruit.  The two books cover similar ground, but they couldn't be more different.  The first part of Why Be Happy, twice as long as the second, is a scraped clean, rewritten, and embellished palimpsest of Oranges:

I have done nothing about finding my past. It isn't "my past," is it? I have written over it. I have recorded on top of it. I have repainted it.

This repainting is much grimmer than the novel, which Winterson acknowledges.

And I suppose the saddest thing for me, thinking about the cover version that is Oranges, is that I wrote a story I could live with. The other one was too painful. I could not survive it.

Oranges, written when the author was just 24, is a lesbian artist's Bildungsroman. In 1960, the six-week old infant who will become Jeanette is adopted by a fanatically religious woman and her mostly absent husband. They raise her in Accrington, a working-class industrial town in the north of England, in a house without books. Jeanette falls secretly in love with literature, and less secretly with another girl; as a result she's exorcised then shunned by her church and driven from home by Mrs. Winterson.

Oranges fits snugly in the tradition of reader-friendly tales of triumph like Rita Mae Brown's 1973 classic, Rubyfruit Jungle. Its wit is mordant, its tone defiant, and its narrative path cuts as clean an arc as an arrow. Jeanette survives her bizarre and difficult upbringing, the "lost-loss" of adoption, to emerge shining and indomitable — made stronger, if anything,  by her difference.

Decades after writing Oranges, Winterson stumbled over a hidden birth certificate in the effects of her father. Long-denied grief overwhelmed her. She began to lose her mind. As she went mad, Winterson kept real-time notes of unfolding events. She attempted suicide, fought to regain her sanity, fell in love with the psychotherapist Susie Orbach, and regressed to infantile helplessness during the harrowing process of finding her birth mother.

Winterson chronicles this journey in parallel with rewriting the story of her Accrington years. Why Be Happy is a mashup of these two narratives, joined at the seam by a two-page Intermission and ending with a short Coda.

Rewrites are as old as literature. In the early middle ages, monks wrote their Gospels on vellum with pigment-based inks. Vellum was high-quality parchment (mammal skin stretched, scraped, and processed to take ink): expensive. Gospels, when the doctrine changed, were not thrown away but scraped bare of the offending text. This reborn vellum, or palimpsest, could then be re-inked with the new, more splendid version, complete with gorgeously embellished initial capitals. However, after a while, the original text often began to bleed through. Some lines, where the original and the rewrite matched, appeared clear and strong and doubly...