Catherine Fairfax MacRae, economist and athlete, loved many things about her life, but her favorite thing in the world was swimming in the ocean, most often at Southampton, where she spent summers with her family.

"Her face would light up when we walked over the beach," said her boyfriend, Andrew Caspersen of Manhattan. "It was the one place where she felt free and at peace with God."

To say that MacRae had everything going for her would be an understatement, friends said. At 23, she was on the fast track as a stock analyst with Fred Alger Management Inc. at 1 World Trade Center. She had graduated magna cum laude last year from Princeton University, where she earned a degree in economics and a special certificate in finance. She played varsity squash, and was equally accomplished at tennis and field hockey, Caspersen said.

Beginning her career in finance last September, she would arrive in her office at 7:30 every morning so she could get her work done in time to have dinner with her family and spend evenings with Andrew and friends. But on the morning of Sept. 11, on the 93rd floor of Tower One, she was in the direct path of a hijacked plane. "She never had a chance," Caspersen said.

At a memorial service attended by 1,000 friends and relatives Oct. 6 at St. Andrew's Dune Church in Southampton, friends talked about MacRae's achievements but "mostly about her love," Caspersen said. Cat, as she was called, "exuded love wherever she went. She wanted to make everybody happy," especially her parents, Cameron and Annie MacRae of Manhattan and Southampton, her 20-year-old sister, Annie, and friends, Caspersen said.

The couple had been dating for four years. Though not officially engaged, "we talked about our future and we were getting impatient," said Caspersen, a law student at Harvard.

For all her accomplishments, he said, MacRae was also funny and self-deprecating. She talked on the phone to her mother at least three times a day, remembered her friends with small gifts and was always on time for an appointment. She grew up in Manhattan and Southampton and graduated from the Brearley School in Manhattan, where she first showed her proficiency in math and sports, Caspersen said.

The couple last swam together in Southampton over the Labor Day weekend.

So many friends wanted to come to the memorial service that her family had a tent set up outside the church. "It was amazing. There was a gusty storm with 40-mile winds in the morning. But then it stopped, and as people began talking about Cat, sunlight flooded the church," Caspersen said.