NEW PALTZ - During the last two weeks of her life, Marianna Cates' husband of 37 years slept in a cot at her hospital bedside. "I was with her night and day," Ray Cates said yesterday. "She was fighting all the way. She was a hard lady to keep down, I can tell you that." Marianna Cates' death on Wednesday at Benedictine Hospital in Kingston ended her fight with breast cancer. It was an on-and-off battle that lasted nearly a decade of her 61 years. But that battle was also the catalyst that helped turn a devoutly Catholic mother who loved the opera and singing in the church choir into an activist and co-founder of the Cancer Awareness Coalition of Ulster County. Following her diagnosis of breast cancer in 1986, Cates became suspicious that the pesticides she said she was sprayed with while working in her garden at her home along Route-299 were responsible for her cancer. She came to consider the area to be the center of a cancer epidemic and became a crusader for the cause, although others, including farmers, dispute the connection to cancer. Susan Cates said yesterday at the family wake that her mother - who also suffered from multiple sclerosis - was sprayed twice by a crop dusting airplane in 1983. Ray and Susan Cates have had cancer. They call themselves "survivors." In 1993, Marianna Cates co-founded the Cancer Awareness Coalition of Ulster County, a group that grew from a handful of members to more than 400 today. The group is dedicated to bringing awareness of the dangers of carcinogenic pesticides. This fall, the group is conducting an independent survey of cancer "hot spots" in Ulster County. "She was constantly working all the way to the end," said Mr. Cates, the Coalition's treasurer. A resident who attended Cates' wake yesterday and asked not to be identified said she contacted the Coalition after a number of members of her New Paltz family developed respiratory problems. "She had an enormous amount of integrity," she said of Cates. "Very few people give back as much as she did. I spoke with her seven months ago and I never knew that she was fighting for her life. But I know this (organization) will live beyond her." During the last three months of Cates' life, she and her husband traveled across the nation to a number of cancer treatment centers in hopes of finding an alternative cure. "We tried everything," Ray Cates said. "I finally just asked a doctor if there were any alternatives. He said, 'No, there's nothing we can do to save her.' "She had a lot of strength," he said. "She never talked about the pain." She is survived by her husband and her daughters Susan Cates of New PaItz and Marie Elana Roland of Vironia Beach, Va.