@jnguy2 As far as I see it, and what this chapter tells us, they both let go of each other rather quickly: him by believing the wrong people and her by simply letting things pass without trying hard to prevent them.
I mean, if you know beforehand that someone is gonna make a bad investment in 3 years time that will make him go broke and will be stubborn about it, is it his fault for making the bad investment or your fault for not trying to stop him from ruining his life in spite of knowing in advance.
The prince still did wrong and should suffer for this... thorougly, but she knew it would happen and despite not wantinf it to happen she simply allowed it while claiming that "future is set in stone", hence why she shares a portion of the blame (but not all nor a great portion of it, the prince was still the idiot here).