It just isn't fair to do that to them. Leave various articles about the Goddess hanging around the house. Look for material that is historically and archeologically correct. Find reading material that is inspirational and non-threatening, and share this information with your parents. Turn on the Learning Channel where features include investigation of matri-focal religions and various religious aspects of different cultures.
Parents have the capability of learning.
This mode of behavior does not shut down when they turn thirty. There is still hope. Your parents can learn as much from you as you can from them. Think about it. Walk softly and carry a big stick.