Count Antoine de Saint Exupéry, celebrated French pilot and author (''Night Flight''), vanished along with his plane during a reconnaissance mission over southern France in 1944. The next year his widow, Consuelo, the bewitching daughter of a Salvadoran coffee planter, poured her grief into The Tale of the Rose, a poetic memoir of their tempestuous marriage. But her discretion led her to suppress the work (it was first published in France last year, two decades after her death). It's clear that Saint Exupéry betrayed her with scads of other women and thwarted her efforts toward independence or divorce, but she still loved him. As he loved her. His last book, the children's classic ''The Little Prince, '' celebrates tiny, proud Consuelo as the Rose. Consuelo, on the other hand, for all her coquettish bravado and embellishments, writes, with style and courage, for grown ups.