I know this from my sister. Weirdly enough, that frustration does feel like she's past the point of suffering where it's still okay to make fun of her. Not so when she falls and genuinely hurts herself, mind you.
I told people to give her time, in these kinds of series its just once your so used to a limited cast when you see new ones suddenly it feels out of place. It reminds me of how people reacted negatively at furst to the 5th mc in kaguya but she grew on people later when she had more time to sink in to the antics.