Game of Thrones, Season 6

Cersei Lannister:
I heard you were leaving King's Landing.

Olenna Tyrell:
That is hardly your concern.

Cersei Lannister:
Your grandson is still a prisoner - you'll leave him rotting in a cell.

Olenna Tyrell:
Loras rots in a cell because of you. The High Sparrow rules this city because of you. Our two ancient Houses face collapse because of you and your stupidity.

Cersei Lannister:
You're right. I made a terrible mistake. I carry it with me every single day.

Olenna Tyrell:
Good.

Cersei Lannister:
I delivered an army of fanatics onto our doorstep. And now we must fight them together. We need each other.

Olenna Tyrell:
I wonder if you're the worst person I've ever met. At a certain age it's hard to recall, but the truly vile do stand out through the years. Do you remember the way you smirked at me when my grandson and granddaughter were dragged off to their cells? I do. I'll never forget it.

Cersei Lannister:
You love your granddaughter. I love my son. It's the only truth I know. We must defend them.

Olenna Tyrell:
I'm leaving this wretched city as fast as I can before that shoeless zealot throws me into one of his cells. If you're half as bright as you think you are, you'll find a way out of here, too.

Cersei Lannister:
Never. I'll never leave my son.

Olenna Tyrell:
What'll you do, then? You have no support. Not anymore. Your brother's gone. The High Sparrow saw to that. The rest of your family have abandoned you. The people despise you. You're surrounded by enemies, thousands of them. You're going to kill them all by yourself? You've lost, Cersei. It's the only joy I can find in all this misery.