So I tried to make a friendship offer with Catherine. She denies.
One round later, she offers it herself, I accept. After that, I propose a 1:1 trade for luxury goods, she agrees.
Another turn later, she attacks me again?! This time with a bigger more up to date army.
But after a good first round where she kills and damages some of my units, she can't decide which city she wants to attack and I kill almost her whole army in the following rounds without further casualties on my side. AI played that war really, really bad.
After almost all her units are dead, she offers me a deal where she offers me basically anything and the kitchen sink in return for a 10 turn peace. I accept, but I sure as hell am going after her capital next.