While Cersei has been getting crazier and crazier over the years, Jaime has become more and more developed and stable.
Instead of Cersei and Jaime as the Lannister siblings working together, we could get Jaime and Tyrion.
His captivity may have cost him his sword arm, but it may have been the best thing that ever happened to him.
Returning to Cersei’s side seemed to set him back, and her announcement that she’s pregnant had the potential to keep Jaime at her side no matter what.