Anne Sullivan faced childhood adversity, contracting trachoma at five which impaired her vision. After her mother died of tuberculosis and her father abandoned them, she entered the Tewksbury almshouse with her younger brother Jimmie. There, she endured harsh conditions, witnessed Jimmie's death from tuberculosis, and underwent multiple unsuccessful eye operations.

Her path changed in 1880 at the Perkins School for the Blind. She learned the manual alphabet and had surgeries that partially restored her sight. Graduating as valedictorian in 1886, she felt a duty to "go forth into active life" and help others overcome obstacles.

As Helen Keller's teacher starting in 1887, Sullivan employed persistence and adaptation. She moved from structured drills to tactile signing based on Helen's interests, leading Helen to learn 575 words, multiplication tables, and Braille within six months. Sullivan believed Helen's main barriers were not her disabilities but the "love and pity" of her family, advocating for disciplined independence. A breakthrough occurred at a water pump when Sullivan spelled "water" into Helen's palm, connecting signs to meaning.

Sullivan's role evolved from teacher to lifelong companion. She accompanied Helen to the Perkins School and Radcliffe College, enabling her formal education. Their inseparable bond saw Helen credit Sullivan with awakening her talents. Sullivan remained Helen's primary support through academics and public endeavors like lecture tours.

Personally, Sullivan married John Albert Macy in 1905, separating by 1914 without divorce. Progressive vision loss culminated in complete blindness by 1935. She died in 1936 with Helen holding her hand. Sullivan was interred at Washington National Cathedral, where Helen's ashes later joined hers.