Personally, and this is the book reader part of me showing up here, I think Jaime has had his last make out with his sister. The show has done nothing on par with Jaime's break up with his sister-lover, but if Cersei ends up being responsible for Tommen's death and goes full Mad Queen, even show Jaime would probably start treating Cersei as a threat, even if the show wants to emphasize he loves her. Book Jaime's all set to be a seperate faction from his sister, and I tend to think they'll probably at least follow his final fate in the show.
Jaime's real distinguishing trait in terms of his honor and morality is that he is a man of sanity, if nothing else. He slew the mad king because the old man went suicidal and genocidal at the same time, not because of his loyalty to his father. Maybe Cersei goes mad, retreats to Casterly Rock, and Dany and co. find they don't have time to bring the lions to heel because, hey, freakin' ice zombies. And maybe Tyrion (who's the only one I can see staying the Stormborn Queen's hand from executing the Kingslayer) begs for his brother's usefulness to at least bring the Rock's manpower to the North.
There's a part of me that likes the idea of having that fever dream Jaime had of "something" lurking in the mines beneath Casterly Rock be a dream of confronting his mad and dangerous sister back in their home, maybe with so,e assistance from Brienne. Heck, maybe if we don't get Cleganebowl, we'll instead get Brienne of Tarth and the Kingslayer against the Walking Mountain.
I hope Varys and Olenna can make those scenes interesting.
