This is not an easy story to write. The sounds of any family wrenching itself apart in public aren't very pretty. The strains of Sen. Edward Brooke's divorce are as harmonious as a dozen fingernails scraping on a blackboard.

In the wake of what is increasingly described as a "bitter divorce" (as if there were a "sweet" one), the Senate may lose a leader, the Republicans a liberal, the blacks a symbol, and women's rights a supporter.

Yet, for just a moment, I want to put aside the issues of the senator's financial "misstatement" and leave the question of his actions to the Senate ethics committee, the courts and even the voters. I want to write something about Mrs. Brooke because she has been in the far background of this drama that has featured the father and daughter in lead roles, as antagonists.

Who, in "all this messy," as she calls it, is Remigia Brooke? There is little in the newspaper library about her life in the years before the divorce. One clipping tells of an accident she had on the way - alone - to her daughter's school sickbed; another describes her at a Red Cross meeting.

But there is little that depicts the woman or the marriage, now more powerful in its death throes than in life.

To put it as simply as possible: The woman I met in her home on a busy suburban street in Newton, Mass., lives in a world as different from the senator's today as it must have been 33 years ago when they met in Italy during the war. Her house is no Watergate apartment; it is homey and modest. The living room, kept off limits from the grandchildren with a kiddle gate, holds a tufted sofa and baroque-style lamps, and an angelic oil painting of her daughter Remi as a young girl. The paneled den is furnished with leather chairs and memorabilia, including a prized 25th-anniversary present: an autographed picture of the men who planted the U.S. flag on the moon. Mrs. Brooke herself, is lively and attractive, 60 years old, the survivor of three cancer operations.

She is not unlike other women we've all known whose marriages were slowly transformed from unions of love to unions of convenience and tradition. Not unlike others who evolved from being happy wives to dutiful wives, hoping that someday that would change back.

She is a woman who built her life around her family, especially her daughters. Her memories are vivid ones, memories of a two-year correspondence with her husband between Boston and Italy. Memories of marriage in 1947 and of living on the G.I. Bill in the poor West End section of Boston in a smallapartment that eventually held a crib in the kitchen and two Salvation Army sofas. She still talks vividly of her difficult pregnancies, and can call up the taste of the licorice she ate and the lines at the health clinic. She remembers, too, the few dreary months she held a job - sewing uniforms in a factory in Northampton, Mass.

In those years, she though of herself as a partner to the husband she called "Carlo" - "maybe not in working, in making money, but in staying at home with the children there was never anybody to help me - and in economizing with the money."

But as her husband moved out and up in the world, Mrs. Brooke remianed at home most of the time. As her daughter Remi describes her, she was the kind of wife who would carry an umbrella down to the car when her husband came home, so that he wouldn't get wet walking to the door in the rain. She even, says Remi with a touch of incredulity, made dinner for him once in the midst of the divorce proceedings.

But the Brookes were, in essence, separated for years. As Mrs. Brooke puts it simply: "My life was over when I was 35." First, they vacationed apart and then lived apart. When Brooke went to Washington, she says, "he was not wanting [me]. He say that not one time, many time. I was covering up all the time. I was saying, I not going to Washington because the climate was not good to me."

The senator was, as they say, seen in public with other women. Mrs. Brooke, however, says: "I never believe in divorce. I grow up in my house like that. We don't believe in divorce. I was all the time hoping he was coming home when he got old like me."

But instead, three years ago, he filed for divorce. The oringinal plea of nofault divorce has turned into a protracted battle to assess fault and to find a legal alchemist who can divide one economic ple into two, each as hig as the first. It's been a divorce in which 29-year-old Remi, taking on the role of the eldest, has risked political patricide in what she sees as defense of her mother.

As for Mrs. Brooke, meeting her, liking her, it's still obvious that she and her husband live in worlds unbridgeably far apart, that they are, understandably, irredeemably incompatible. Telling Mrs. Brooke's story is different from taking her side. In a bad marriage, there is no more a single victim than there is a single vilian.

Their marriage should have ended legally the way it ended emotionally - with disappointment, yes, but with distance, coolness. Instead, there is "all this messy."

Decent people are at their least attractive in divorce, warring over ailmony, property, taxes - money. It is not in the nature of the event to show constrain or consideration in the midst of dissolution.

So, the private side of this story is of a unit dissolved into egocentric factions, a family divided into Me-Firsts. Not an easy story. Perhaps the saddest footnote was offered by the Brookes' three-year-old granddaughter. In the den, Tamara saw a picture of Sen. Brooke in a newspaper story detailing his troubles. She smiled innocently at her mother, Remi - the woman who has helped put him on page one - and then said cheerfully, "Look Mommy . . . Granddaddy!"