This 1000%, plus she says "don't try to handle it alone" and what has she been doing this whole time? How many secrets is she keeping from everybody? The reasons for her not to tell anyone that she doesn't have magic feel so forced. Maybe in the beginning, I could buy that she was worried about losing the trust of her family but that excuse doesn't work when there hasn't been any real focus on her worried about gaining their trust, keeping their trust, or doing anything to improve the relationship. She's been so blase about it, as if it's the status quo.
Not telling the Duke in the moment felt believable, because there was a spy and he warned her about it. But she's had ample opportunities to tell him until now and still hasn't. And I'm not buying the excuse of "well, she tried and they were interrupted!" No, she only ever makes an attempt when the "mood is right" which is ridiculous and she's only attempted to tell this secret in a private setting once, right after the bomb earring incident. Even then, that doesn't fully count, because the windows were shattered, so anyone could overhear. I've seen kid movies with more believability.
And say she doesn't feel comfortable telling them. What about Carol, her trusted maid? What about her new secretary and her sister? She trusts them more than anyone else but she won't trust them with a threat to her life?
I feel like the mc's priorities are skewed. I know she doesn't trust Concordia, but she can't say "you can't bare this alone. I was like you. You need help" to Concordia & then not take it as seriously as Concordia looked. I understand she needs those crystals to heal herself, but her being at the meeting place seems more time sensitive at the moment. Why is author waylaying her with this proposal? It can wait a little