The Bass marriage ended abruptly in 1986, when Mr. Bass left his wife for the socialite Mercedes Kellogg. The tabloids reveled in every detail of the romance, which reportedly began at a formal ball when Ms. Kellogg threw a dinner roll across the room at Mr. Bass.
The divorce, in 1988, left Ms. Bass with a settlement estimated at $200 million. She was able to hold onto the house in Fort Worth, as well as a Manhattan pied-à-terre on Fifth Avenue and its lofty contents: paintings by Monet and Mark Rothko, and an original bronze cast of Degas’s “Little 14-Year-Old Dancer.”
In subsequent years, Ms. Bass became one of New York’s most respected philanthropists, supporting, in large but unflashy ways, the New York Botanical Garden, the Museum of Modern Art and, especially, the New York Public Library and its Jerome Robbins Dance Division, which is housed at Lincoln Center and holds the largest archive on the history of dance in the world.
Ms. Bass never remarried. She met Mr. Lethbridge, an accomplished artist six years her junior, in 1993. He specializes in large-scale abstract paintings that feel rooted in nature, variously evoking winter tree branches, churning waves or rosy dawns.
In addition to Mr. Lethbridge, Ms. Bass is survived by two daughters, Hyatt Bass, a novelist, and Samantha Bass, a photographer.
As a board member, Ms. Bass was sometimes described as brusque and implacable. In 1987, as a longtime trustee of the Fort Worth Art Museum, she was blamed for a high institutional turnover: Within a decade, three directors and an interim director had arrived and departed in short order. Even those who admired her exacting standards could be bothered by “the Bass body count,” as Texas Monthly put it, referring to the arts administrators who had failed to cut it in her eyes.