Faieza Omar Desai, the wife of Western Cape High Court Judge Siraj Desai, died at the age of 58 on Thursday morning.
She lost her battle with a rare type of lymphoma, said family spokesperson Rafique Modack.
Lymphoma is a cancer of the lymph nodes and lymphatic system, the body's disease-fighting network.
She leaves behind her husband, sons Tariq (31) and Azhar (28), and daughter Aniqah, who will turn 27 on Friday.
"Faieza lived a full life. She was the party agent for the ANC in the Western Cape for every election since the first democratic elections in 1994," said Modack.
He said she was an activist in her own right and supported her husband so that he could play a greater role in society.
Faieza, who held a masters degree in public health, was a nurse by profession and spent most of her later life as a public health practitioner.
She was also very athletic and participated in running events.
"She climbed mountains throughout the world, including Mount Kilimanjaro and Base Camp Mount Everest, among others," said Modack.
Her body was expected to leave her home in University Estate on Thursday afternoon for a funeral at a mosque and then a burial at Mowbray cemetery.