I don’t recognize my friend anymore - need urgent advice, please help

Assalamu alaikum. I’m really worried and don’t know what to do, so I’m asking for honest advice. One of my close friends (29F, Muslim) has been talking to a man (34M, Muslim) for about a year. He’s studying in the US on a student visa and they met through someone we both know. Long story short, she started speaking with him while he was still married. He told her his marriage was unhappy and long-distance, that they only saw each other every few months. Apparently when they met things improved, but he made it clear to my friend he felt miserable in the marriage. He even went out to see my friend on Valentine’s Day and left his wife at home knowing she was there. His wife had helped him financially at times - even contributing toward a car - and he painted her as the problem, saying she didn’t take care of herself, didn’t eat right or exercise, and so on. My friend kept talking to him despite knowing he was married. He told his close friend that my friend was “meant for him,” while still married. Now he is divorced and my friend plans to marry him in March. Because of this relationship, my friend now fights with her parents constantly. Her parents have asked that she not meet anyone before marriage and that’s their one request, but he pressures her to go out and meet him. Her parents are heartbroken - they cry and ask Allah for forgiveness for their daughter. Since meeting him, my friend’s life has changed a lot. She’s been caught drinking and smoking weed; I don’t know if she prays or reads Quran anymore. She has stopped respecting her family’s wishes. He has argued with her mother on the phone and even disrespected my own mother. My friend is always chasing after him and seems to care only about him. She’s become a mess and stopped taking care of herself. I keep having dreams of her crying and telling me he mistreats her. I’m exhausted. I keep trying to help but she pushes people away and won’t accept advice. He’s also spoken to other women and gone out with them, and she still stays. I’m afraid she’s become numb and won’t listen to anyone. My parents and her parents have tried everything to stop this. She’s a doctor with a good job, and I wonder if she thinks her status lets her do as she pleases. I fear she has lost her fear of Allah and might be too far gone. Does anyone have any sincere suggestions on how I can help her without pushing her further away? Any gentle Islamic advice, duas, or ways to reach her heart would be appreciated. JazakAllah khair.