She's not really in the mood for chocolates.
She's in the mood to collapse dramatically on the floor and wonder if she should, in fact, have, immediately betrayed Keltham to Otolmens who would crush him.
This is not an important question to answer, in one sense. She can't do it now. The error, if it was an error, was made due to intense time pressure and incomplete information about her past self's plans and panic and the risk of being mindread and love for Keltham and guilt over having harmed him so badly and existential horror at the thought of him being casually annihilated for a thought he might not even in fact be thinking, and she doesn't exactly think she'll make similar errors in the future. She's sure never ever ever going to love anyone again.
The obvious analysis here is that yes, she should have immediately betrayed Keltham, or at least have refused to step out of the Iron Dome until she had his promise she could oppose him if she saw fit, which he wouldn't have given, at which point she'd have betrayed him to Otolmens.
(Why does it even come to her to betray him to Otolmens? How is Otolmens not carefully watching the situation already! Wasn't Broom supposed to be handling this?)
(Broom, who Osirion freed because they don't enslave halflings. It would serve everyone right, in some sense, certainly serve Otolmens and Cheliax right, if Broom, freed, decided to go travel the world or buy a house or something. Or maybe he's here, and just hoping he won't have to stab Keltham. Either way, if Keltham isn't worrying about Broom Carissa won't bring the possibility to his attention).
The less-obvious analysis here is that this way, she might be able to talk Keltham into a version of his plan that is actually better than the status quo, and it all depends on the probabilities, which she's poorly equipped to even begin to estimate. But Snack Service thought something good could happen here, something for which Carissa mattered and Carissa's status in Hell mattered, and -
- she thinks everything Cayden/Nethys has done has made this harder for Keltham to pull off? Otolmens picking Broom in the first place was a response to Pilar and Ione being picked; She's paying the situation closer attention. Nefreti said that the deception would've gone on longer without Cayden/Nethys's interventions, and if that's so, then when Keltham departed he'd have been richer, and Cheliax been less impaired in pursuing him, and he wouldn't have had the prospect of his children rushing him to solve this prematurely, they'd already have existed.....
If Cayden and Nethys were aiming at the destruction of the world they could have probably done it, from this starting point. So they're aiming at something else. And - she's not sure this logic is valid, but it does feel like probably if she were the kind of person who Nethys knew would instantly report Keltham, then some other person meets Keltham where he lands instead, some person who doesn't feel so strongly about the world not ending -
This is, perhaps, a question to return to when she's a god. If she's a god. She sure is making a lot of plans premised on her godhood, lately, for someone who does not in fact possess godhood and is actually just a fifth circle wizard with more money than fifth circle wizards usually have.
Perhaps she is staring at this because for all that it hurts, it doesn't hurt as much as staring inward and figuring out who she is and what she isn't and what she's done.