Strength for a Grieving Family : Tragedy: An army of volunteers joined the search for slain nurse Kellie O’Sullivan. ‘A lot of people figured it could be their girlfriend, their wife,’ the victim’s boyfriend says.

Kellie O’Sullivan’s disappearance two weeks ago plunged her family and friends into shock.

But by the next morning they were on the move, printing and handing out 20,000 flyers with her photo and asking for help in finding the 34-year-old Westlake Village nurse. Soon a small army of volunteers had formed, willing to give more generously than O’Sullivan’s loved ones could have hoped.

At the peak of the search, about 275 civilians linked by cellular phones joined more than 30 Ventura County Sheriff’s Department personnel in a net that spread across 170 square miles of the Santa Monica Mountains.

People lent telephones and helicopters to the search. Party suppliers provided colored crepe paper that searchers tied to brush to mark the areas they had searched, a different color for each day the hunt continued. O’Sullivan’s neighbors prepared hundreds of sandwiches each day to feed searchers.

On Sunday morning, two people who had joined the search only 45 minutes earlier found the decaying body of a woman clad in a white nurse’s uniform in a rocky notch off Mulholland Highway.

The Los Angeles county coroner’s office confirmed Monday that the woman was Kellie O’Sullivan and that she had been shot to death.

Bound tightly together for 12 days to focus on the search, O’Sullivan’s family said they were relieved to finally learn her fate.

“I’m still numb,” said her mother, Sharlene Cunningham. “I don’t want to collapse. I want to be here for all the people who were here for Kellie.”

“It’s been incredible, the donations and just the contributions of people’s time,” said Kevin White, O’Sullivan’s boyfriend. “I know dozens of people who didn’t go to work all week. A lot of people figured it could be their girlfriend, their wife.”

Her ex-husband, Cliff O’Sullivan, said he told their 5-year-old son Sunday night what had happened.

“He told me a couple days ago he had a dream that the bad guy killed mom,” O’Sullivan said. “Last night I told him he was right. He put his arms around my neck and he said, ‘I believe you, Daddy.’ ”

The household where Kellie O’Sullivan lived had quickly transformed into a command post. It dispatched searchers into the mountains, supplied them with food and fielded hundreds of calls from reporters, detectives, well-wishers and tipsters.

There were false alarms and freak discoveries. Searchers who heard moaning in a canyon found a wounded bobcat. Others came upon a fully rigged, clandestine narcotics lab that was pointed out to detectives for investigation. The searchers discovered dozens of campsites used by homeless people.

At times, worries about the missing woman’s fate would overwhelm the family’s sense of purpose, Cliff O’Sullivan said, and they had to talk each other out of immobility.

“Each of us would go through a well of desperation, and the other night Kevin . . . helped me kind of push through it. I have a lot of respect for him,” O’Sullivan said. “In that entire 12-day period, none of us fought with each other, which when you have an entire group of headstrong people together is unusual.”

Peter Greaney, who shared the house with White and Kellie O’Sullivan, said the group tried to avoid expressing their worst fears--that O’Sullivan would be found dead.

“I hoped she wasn’t suffering,” Greaney said. “I had no illusions from the start--most of these cases I believe turn out badly. . . . But I couldn’t say anything about it because there’s always hope.”

Through it all, the family was overwhelmed by the support from people who had never met O’Sullivan and the extensive resources focused on finding her.

“We can’t possibly say enough about the volunteers,” said her mother. “I felt like I was in a little city, or on the set at the filming of ‘Ben-Hur,’ with the helicopters and telephones and everything. . . . It was about unity. It was about finding Kellie.”