I am sorry you have to go thru this. Unfortunately, racism is very strong here in the US. It does work both ways. Being of mixed racial descent, I tend to get it from both sides. And unfortunate as it seems I often get it from the places least expected. I have learned to be patient and for the most part look past it for a bit. Soon enough they come around whatever side is sending out the negative. It is as they have to test you out a bit. And too, the older generation takes a lot longer. they have seen too much and really we have not as a US nation started fixing this gap but within the last 100 years.
I am sure with the State Zimbabwe (SP) is in, that it has to be very difficult to get past things you may have seen prior. So with that said, give them some time and be very accepting of him (if you want to be) and hopefully she comes around and he will ride out the storm. And if she never does, it will be her loss. I only see the unacceptance splitting her from him and the 'loves" will move closer.
We all as a nation and as a world have come so far..and some days it feels as if not at all.
Decki