Night after night for months, Alex Webber stitched her way through a pile of tiny colored beads, transforming them into an intricate mosaic depicting a pot of boiling crawfish.

It was her costume last year for Mardi Gras, the celebration that had routinely drawn her back to New Orleans after Hurricane Katrina. She held onto her creation for whenever she needed reminding of her capacity for withstanding tough times, and of the city that always helped her through them. Lately, that has been often.

Twenty years ago this week, Katrina took her home and job and essentially set her adrift, leading her to leave the city she had called home for roughly a decade. She eventually settled in the mountains of western North Carolina, where she raised her daughter, remarried, started a business, lost it to another natural disaster and opened it again.

Still, New Orleans has never felt that far away. She routinely cooks Camellia red kidney beans, visits her friends there as often as she can and maintains her membership with one of the Mardi Gras krewes that puts on parades and parties in the city during the Carnival season.

“I didn’t stop loving the city,” Ms. Webber, 55, said. “I’ve loved her ever since I met her.”

Katrina forced a brutal calculus upon hundreds of thousands of New Orleans residents. Their affection for the city was suddenly balanced against the daunting struggles that they would confront if they stayed in a place where physical devastation and emotional trauma were so widespread.