You can take preventive measures to prevent her from lodging any false complaint against you people by lodging a NC from your side before local police in advance expressing your fears about her suicidal threats and her aggressiveness due to which you anticipate risk to you and your parents.
At home you can try to convince her, if she doesn't listen and rejects all your efforts to pacify her, then you can ignore her but keep a constant vigil on her activities.
You can't make her alright if she's adamant and rigid in her behavior.