mariakha

I remember the plot vaguely. It’s about a teenage girl who has blackouts but when she does she actually travels to a parallel universe. She decides to cut herself to see if it shows when she blacks out however her parents then send her to a psychiatric hospital as they think she is unwell. Whilst at the hospital she befriends a male staff member close to her age who helps her with the blackouts I do remember a school prom? And I think she had a younger sister who only visited once