They'd had something of a scene. Finally Cherry Boone promised her fiancé, Dan O'Neill, that she would never again gorge herself with food only to throw it up. Dan took her at her word—after all, if you couldn't trust Pat Boone's eldest daughter, whom could you trust? As he drove off into the night, Cherry walked into the family's Beverly Hills home and stared at the meat scraps left for her dog, Summa. Minutes later, returning unannounced to the house, Dan remembers witnessing the most "revolting and pathetic thing I'd ever seen." His wife-to-be was sitting on the kitchen floor, eating out of the dog's dish. "I nearly broke off the engagement," he remembers. "But I realized she must be sick, and I loved her enough that I wanted to help her if I could."

Dan, now 34, and Cherry, 28, were married in 1975 as planned. But, as Cherry recounts in her forthcoming book, Starving for Attention (Continuum, $12.95), it took Dan two difficult years to get her the help she needed in her struggle with anorexia nervosa and bulimia, emotional eating disorders that affect nearly 100,000 young women each year.

The O'Neills now believe that part of the problem was Pat Boone himself, who made repeated efforts to help his daughter but recoiled from Dan's idea that she required psychiatric care. The singer also bristled at Dan's assertion that Cherry needed to leave the Boones' L.A. home and move in with his parents in Shelton, Wash. "I was not only fighting a father-in-law," remembers Dan. "I was fighting Pat Boone, an American institution. I was telling Mr. Cookies-and-Milk what was best for his daughter."

Actually, a more difficult adversary was Cherry herself. The eldest of the four Boone girls, she had started performing with her father at age 5. By 1970, at 16, she was a regular on the family's stage and TV appearances. She was a natural beauty, a straight-A student at Westlake School for Girls in L.A.'s Holmby Hills, seemingly a model member of America's model family. Yet she was also subtly burdened by being Pat Boone's daughter. "He's a good father," says Cherry. "But it was the way people responded to him and the expectations they had of his children that got to me." On TV her 140 pounds on a 5'7" frame struck her as hefty, as an unsightly blemish on her father's image. "I thought my father was perfect in every way," says Cherry, "so I wanted to be perfect too."

It was to "perfect" herself that she started dieting and exercising. When her parents and friends praised her new sleekness, she quit eating altogether. In her disturbed mind, as she sees it now, starving herself not only gained her attention and won praise for her father, but it also gave her a feeling of power. "I was controlling a part of my life," says Cherry, "a life which was controlled for the most part by other people."

It wasn't until she was 17 and weighed a mere 92 pounds that Pat and Shirley Boone realized there was something seriously wrong with their daughter. They insisted that she eat. Cherry responded with a life full of lies. She would gorge only to vomit. She shoplifted laxatives because she was ashamed to be seen buying quantities of them. She became addicted to diet pills—with the result that at age 18 she weighed 80 pounds and found herself lying near death in an L.A. hospital. Her parents subsequently spent thousands of dollars on doctors and institutions to fatten her up—all to no avail. "You can't beat anorexia by forcing someone to eat," says Cherry. "They will just throw it up. You have to treat the reasons why someone became anorexic in the first place."

Finally, in 1977, by which time much more was known about anorexia, Dan O'Neill prevailed. Some six months after she had started psychiatric treatment, Dr. Raymond E. Vath of Seattle had coaxed Cherry to come to grips with her feelings about herself. After seven years of near starvation, she began to eat properly. Today she weighs 110 pounds and consumes 2,000 calories a day. "I eat a lot of nuts and raisins," she says, "and I have a passion for guacamole and fried tortillas." No longer interested in showbiz, she exercises moderately, attends Mass (she and Dan converted to Roman Catholicism), addresses civic groups about anorexia, and cares for her 1-year-old daughter, Brittany.

However, she still has differences with her father. A fundamentalist Protestant, he does not fully approve of her conversion to Catholicism: "I think they have taken on a lot of excess baggage in their spiritual life." Nor is he wildly happy about her book: "I was disappointed that she had to focus on so much of the unhappiness in our family," he says. "A lot of the happy aspects sort of got left out." Despite those disputes, both Cherry and Dan, executive director of Mercy Corps International, a refugee-relief agency, insist that their ordeal has brought them closer to the Boones. "My relationship with my parents is healthier than before because I'm my own person," says Cherry. "My identity no longer rises and falls with the Pat Boone family."