Asks about divorce! My favourite, thankyouthankyou 💙
SO I don't have a super 100% clear timeline on post-canon things, because I prefer to give myself room to manoeuvre in case I come up with better ideas down the line.
BUT my current vision of things is that the first cracks begin to show soon after the game is over when Lucanis returns to Treviso to actually act as a First Talon, and not just have the title without any responsibility. That's when he finds out what it's like to run a severely weakened house and how exactly precarious their position is (imagine that your first act as a First Talon is publicly forgiving a traitor who wanted to give up your city to the vints. bet that's gonna score Lucanis sooo many popularity points with all the other crows).
And he kind of hides the extent of how bad it is from Ghilasara (she hides soo many things from him too and is a hypocrite actually, but that's another post). So he becomes more distant and avoidant, because it's easier to just not meet each other rather than meet and have to lie to her that everything's alright. But she'd put the pieces together relatively quickly, and then it's only about waiting for the right chance to bring up how much this job wears him down, and how he really shouldn't be doing that, probably. Because that job is going to kill him, and she can't take watching him die.
Cue divorce #1 when some undisputable evidence about the Dellamorte hardships comes to light, things blow up, she realises that he will always put his job as First Talon before anything else (well, she will also always put her job as First Warden before anything else. as I said, a hypocrite <3), and that's the only way things can be. In my mind, the first break-up happens within the first two years post-canon.
Then they get together within a year because they can't stay away from each other (there's a fic about that!), then they break up, then get together again... A very long and tragic story.