Hi,
I know the feeling of having increased health problems. As it is, my medical-aid has been depleted since April this year already.
Unfortunately, as far as I know, the answer to your question, is yes. The government sees a married couple as a partnership. Any debt incurred, falls on both parties regardless of the fact that it was incurred from a joint-account or not.
I hope it's nothing serious and I wish you and your wife all of the best with your studies.