Your interactions with the white sector of the country have been hurtful and difficult. What concerns me  though is that the gist of your article is that racism exists from white to black and that is its definition.
From the rantings of the ANC and EFF leaders it is quite obvious that racism from blacks is evident against whites.
And of course there are other very large cultural  groups that you do not mention: the so-called "coloured" and the Indian population who arrived here as either slaves or indentured labour. And let's not forget the refugees from Somalia and elsewhere North who are derided by local Africans as “makwerekwere”.
So yes, we certainly do need to talk about racism in all its aspects and as Ms Thlabi says: 
"not all white people are racist but that does not mean that racism does not exist" and my caveat to that is "not all black South African people are racist  but that does not mean that racism does not exist in every sector of society" 
And how will you change it?