It sounds awful and she obviously needs help, but you can’t help her when she’s like this. She needs professional help, someone who is detached from her and knows what they are doing.
Coke is only going to make her issues even worse, it messes with the neurotransmitters in your brain, and if she already had mental health issues this will be even worse.
I’d go so far as to suggest that she needs sectioning, please get some professional advice yourself. Icarus are really good 🙂