I'm sorry to be reading all this. I'm so sorry about the surgery results. So often when a woman is diagnosed with ovarian cancer, they find it has already spread by the time they do surgery. There aren't many early warning signs with ovarian cancer. Your aunt will be given some options based on what they found during surgery.
If it was me, I'd want to know the truth of my condition. You are going to have to be strong now. Be supportive of what your aunt decides for herself. She can only make real decisions if she knows the truth about her condition.