Something to keep in mind is that there are a LOT of English speaking people in SA who do not feel Afrikaans or English, only South African.
There may be a misconception amongst Afrikaners (and in other cultures in SA) that because you speak English you feel some sort of an allegiance to England.
This could not be further from the truth. There are in fact only a small percentage of English speakers who are eligible for a British passport or who feel some bond to the UK.
In my case, my father is German (I have an extended family in Germany, however I feel virtually no bond to Germany either), but my mom´s side has been in SA for many many generations, with English, French and Afrikaans heritage.
I feel only one thing, South African, and the fact that my mother tongue is English is purely arbitrary.
I do feel that there has at times been a little friction between some Afrikaners and some English.
I can think of some reasons:
1) Afrikaners have been more willing to speak English than English willing to speak Afrikaans. Afrikaners would generally have to speak English in social situations within a mixed group of English and Afrikaners.
2) Government positions were reserved almost exclusively for Afrikaners (accompanied by a certain resentment by the English - and of course the other African cultures.) This also brought one culture, the Afrikaners, exclusively into the line of fire with regards to Government policies and incompetencies.
3) The English also created their own economic community, with English speaking companies favouring English speaking employees.
These have been my experiences, feel free to add, or disagree.
I do also feel that now, more than ever before, the relationship between English speakers and Afrikaans speakers is the best it has ever been.
It´s great when you hear English speaking people (overseas and at home) bragging about essentially Afrikaans things like boerewors, biltong, Ouma´s rusks etc. etc.
But then, like I said, I´m South African first and don´t really think of those things as being from Afrikaans or English culture but just from MY culture.