You could probably make that drive in a day... If you've got that much time on your hands. From Orlando to Blairsville, GA is 10hr drive, and I think we go through about 3 tanks of gas to get there and back. And that's way cheaper than buying a plane ticket, especially for two people.
Have you looked at flying out of different airports?? If you're in the Miami side, look at MIA, FLL, and WPB. When my mom went to Texas it was way cheaper to fly out of FLL, but twice as much to fly back, so I saved 20$ by flying her to WPB.