I'd never noticed that Crais was actually crying when he was talking to Talyn after Aeryn's death.
I knew that he was struck by her death, so soon after he'd offered her a way from Moya if everything was truly lost, but not the tears.
Guilty for driving her away from the only life she knew, but he knows that she's grateful to him for doing that too since now he knows the freedom that he's given her by doing it.
Finding a purpose, to an extent, with Talyn. He does care for the ship, and knows how Tayln feels for Aeryn too through the link. Crais has probably been privy to those first moments when Aeryn first stepped foot on the bridge. He's kind or reaching out to her to rebuild the family he'd lost when the Peacekeepers took him and Tauvo. But she's also something he's grown accustomed to since it was a large part of his life longer than his real family.
Aeryn is a culmination of both lives he's lived, domestic and military, and it's the only thing that he's found like that. So he's mourning for everything when she died.
I'll probably expand on this when I get back home in an hour or so. I just wanted to get it out while it was fresh in my mind.