There are, perhaps, some reasons that Arthur hasn't heard that the table has been destroyed, or that Nathan's been shot. No one's sought him out, certainly, nor has he been very visible.
The truth is, he knows something is coming, soon and big. Lexi coming was wonderful, but also disorienting, and drove something home to him.
He very well might lose Adia, once whatever it is happens. For a dozen different reasons, but he isn't sure they're all things he can stop, try as he might. And he's not sure how he can bear that. Because as much as he loved his queen... he's falling harder and harder for Adia, here and now.
So. If their time is short, he's going to make the most of it.
Which is why, when Adia comes home, there will be a candelit dinner, with wine, all set out. He managed a roast, with some potatoes, but bought the dessert, because he didn't trust himself to bake. Still. It looks very nice.