I would advise against becoming involved with your ex-roommate again. Living with her was a mistake. She threatened you and subsequently began stalking you after you moved out. Fortunately, you were able to escape before she became violent.
Even if you tried to help, there’s little or nothing you could do. You’re not a mental health professional. If you tried speaking to her family, it might only make her angry. That might make you a target and she might try to hurt you.
It is wise to stay away from her. You should continue to avoid contact with her. In fact, if she does try to contact you, call the authorities. Never underestimate the dangerousness of someone who threatens you, especially when that individual is mentally unstable. Stay safe and please take care.
Dr. Kristina Randle