A look at the trauma suffered by--and the possible courses of action open to--those whose parents divorce after their children are old enough to vote. It may be lacking in compassion to question the need for a self-help book addressed to the adult offspring of parents who divorce at retirement age. (So prevalent are these midlife breakups now that there is even a term for it, ``gray divorce.'') True, American adolescence is prolonged. But is it legitimate to demand that parents stay together for the sake of the kids when the kids are nearing 30? With that question in mind, this is a pretty good book of its kind. The authors (Fintushel: a free-lance writer; Hillard: a clinical psychologist) address the questions of the pain caused when the familiar patterns of relationships are broken, when family myths are exploded, and when friends ask, ``Why are you so upset? You're grown-up.'' Fintushel's parents divorced when she was 22, and there is an evocative recounting of how her ideal family ``blew up in my face.'' Interviews with other adult offspring of late divorces substantiate the importance of the familial fantasy in shaping lives and character. Hillard contributes advice on dealing with the new relationships that must be formed after such a split, how to avoid destructive patterns in your own marriage, and even how to plan holidays. The wrap-up is that with time and effort, the new lives can be liberating for both parents and grown-up children. The question remains whether grown-up children should be waiting for a parental divorce to launch them on the path to liberation.