
Background Info
My sister went to hospital voluntarily during her first 'psychotic episode' around New Year, suffering acute anxiety and delusions. She had been presenting signs of instability for around a month, since our other sister (her twin) disclosed that she had been raped, which was enormously traumatic for us but especially for her twin. I believe her symptoms were triggered by this, built on the cumulative stress of living with an abusive father when we were kids, and living with our mother, who is mentally unstable herself (I think perhaps bipolar?) and has never gotten help... She was sectioned under section 2, institutionalised and put on quetiapine and sertraline.
Current Crisis
Fast forward 3 months. She's still on the meds but has not received ANY one-to-one cognitive or talking therapy with a psychiatrist due, they say, to 'staff shortages'. But she is still on the meds. I feel like I've lost my little sister entirely. She used to be kind, calm, mature and very empathetic. Now she swings between hyperactivity, panic and agression, and this zombie-like state where all she wants to do is sleep and be left alone. I and her twin were always the ones she'd open up to, but we both feel like our relationship of love and trust has disappeared somehow. She's also showing physical side effects of the quetiapine - such as restlessness, uncontrolled limb movements, cold sweats, confusion, irregular heartbeat, tiredness (she still suffers from insomnia) and irregular heartbeat. Online it says that in such cases a doctor should be consulted immediately and most likely, the drug discontinued - but none of the staff there seem to be taking them seriously at all.
I hooked her up with an independent advisor to represent her, which was good in the beginning but now she is so volatile she can't hold onto a consistent opinion (i.e. about her meds, or where she wants to be,) for more than a few hours, so there's not much for him to 'represent' anymore. I feel like she's not able to give informed consent but I'm afraid that if we make that argument, they'll just section her again and keep doing what they're doing, rather than empowering us to look after her.
The reality is, by the time they took her off section, giving her the power to make her own choices, they'd already robbed her of that power by drugging her down. And now things are going from bad to worse...
It's so hard to know where to turn to in a situation like this, because we have so little legal power and don't know who to trust. We can't rely on either of our parents. I am 24, so a legal adult, but not a legal guardian... I feel like I'm the only one with the resources and awareness to guard her interests, but I have little legal power to do so. But whatever it takes, I have to get her out of this dark place somehow. She recovered quickly from her one and only 'psychotic episode' (which I'm not even convinced was a psychotic episode, since we have a complex family history of seizures and epilepsy and these can be easily confused...) but she's been getting worse since she's been there, not better. And can it even be legal for them to just drug her up like that and leave her without talking therapy???

Feel so lost and helpless. If anyone has had any of these experiences, or can offer any guidance, I'd be forever grateful.