[She'll have all her feelings back in order later, okay, but she can at least right herself for now and take his words at face value, because...]

Right, I still have to give you and Cherry a grand tour of my place. And this place isn't half as pretty as you could ever make it. It'd be stupid just to give up before you've beautified everything.

[It's an excellent reasoning as far as she's concerned, however temporary. Whereas Zagi had felt like one of her brother in arms, Mettaton's just... kind of become someone she's used to be around and would be really sad if he died so don't??]