I wanna say that she knows that the heroine is probably also reincarnated but she's just choosing not to think about it...
If she is reincarnated, do you think it's with or without her original memories? Even if it is with those memories, she may just not have the confidence or maybe she didn't play the game so doesn't know the choices.
Just as clarification, i didn't read the novel so i have no knowledge of the source material. This is all just personal feelings and conjecture.