I actually think her reaction is normal here, and pretty believable. She clearly has trust and abandonment issues, and has trouble believing that Yoshida’s generosity is truly without a catch or that she couldn’t be replaced. This is a real thing that adolescents can face.
But hopefully this doesn’t evolve into something romantic on both sides. They both deserve a healthy relationship, and a huge age-gap romance based on dependence is anything but that.
@Kinji I can say with absolute confidence that every single person in this thread deriding her as a thot or used goods or whatever has never seen a vagina in person.