Becca and Ulli: they're neighbors, young mothers, one-time co-residents of a Cape Cod summer house, best and fastest friends. But they are also very different women. Ulli is Swedish, an ex-model, married to handsome TV anchorman John, and able to do well at just about anything. Becca, an ex-Jewish-princess and Bennington dance-major, is married to unfaithful sociology prof Gerry--and she's inept at the domestic arts. Becca's talent, rather, is for response--to Ulli's cool perfections, to childbirth, to her own gauche Florida parents. And though first-novelist Jaffee makes these responses bright, witty, and appealing, what seems at first a chic cartoon becomes something much darker. Ulli was raped at 14 by her mother's then-lover; Becca's marriage is breaking up as Gerry admits his infidelities. And the book drops into a completely minor key with the news that Ulli is dying--of brain cancer (which comes on while Becca is in Europe). Thus, Becca must live out a friend's dying--and finds herself confusedly consoling Ulli's husband John: ""The problem with surviving, thinks Becca in Ulli's bed. . . is that one must pack up one's guilt like fragile crystal, and carry it in the body, a soft sack, a vessel unsuited for such a long arduous journey."" True, Jaffee doesn't quite have the narrative skills to downshift smoothly, so her first book seems to have a number of false bottoms. But, with comically wise attention paid to the unstable scales of friendship, this is, in all, a strong and tender fiction debut.