I grew up in an anti-apartheid home in the 50s and 60s. It was very rare to be against racism in those days. Even more rare was for a woman to join a political women-only anti-apartheid organisation - the Black Sash. You can google that.
So I grew up knowing that racism was wrong.
When I started dating, and for all of my life in South Africa, until I left, the minute I said something about apartheid being wrong, there would be an uncomfortable silence, and then the topic would be changed.
Politeness made me abide by the social convention not to talk about something that someone else did not want to talk about.
In 1966, Nobel prize winner, Desmond Tutu came to speak to our school. Our head mistress (later, Lady Elizabeth Johnstone, wife of Lord John Johnsone, the last British High Commissioner of Rhodesia before UDI) had invited him. At the end of the school year, half of the students left...
It stunned me. These were the children of the rich and upper classes - yet still they supported apartheid.