Complex sentence: The current King has kept this ceremony, called the "Reed Dance" but not chosen a wife, instead using the ceremony to promote abstinence until marriage as a way of preserving Zulu culture and preventing the spread of HIV/AIDS.
Split into simpler sentences: The current King practices the ceremony, called the "Reed Dance", but has not chosen new wives recently. Instead, he has used the occasion to promote abstinence until marriage as a way of preserving Zulu culture and preventing the spread of HIV/AIDS.