Seriously, Violette doesn't really want to go away, be a nun, or whatever. She's just trying to find the path of least pain. What she REALLY wants is to be loved, but she's also in a position where she's been so hurt she finds it hard to accept love. Especially from MaryJun. Even in the original timeline, she was just trying to find meaning in her life and she finally snapped. Seeing how her mother abused her this chapter adds another layer to her miserable life.
Father is a scumbag but I did see someone mention that he was abused too - and he's taking it out on Violette.
MaryJun - I think people are being too hard on her. I think this chapter she finally realized her sister is being treated unfairly, and inviting her for tea is her way of trying to reach out to her. I don't think she completely gets how Violette feels yet, but I think she does love her and is looking for ways to express her love.
The prince - yeah. Basically, the hottest girl in the kingdom relentlessly threw herself at him and annoyed him to death. Now she seems to have moved on and is keeping her distance, and he misses the attention. EDIT: Also, her new, more reserved personality makes her even hotter!