@Historylover, I'm sorry to hear that your now starting to see your situation as captivity. I have no such experiance with psych wards - I've only ever had pre-booked daytime sessions with therapists, so I can't offer much personal insight.
Your in Victoria, right? I googled these people: https://www.imha.vic.gov.au, who apparently advocate for Victorian mental health patients and try to insure their wishes about their own treatment are respected. Apparently, you can call them on 1300 947 820, between 9.30am and 4.30pm, 7 days a week. If things start getting a bit too oppressive for your liking, maybe they might be able to help?
Also, whenever anybody tries to make you do something you don't want to do, ask them about your legal rights in that situation. It's my understanding that the therapists/nurses/orderlies, ect. are obligated to be completely open and honest in the face of such questions.
In regards to your concerns about your "love to chat", and thereby letting slip information that you don't want to let slip - that reminds me of my time with my own therapist. I realized all too late that it was hazardous to give her deep insight into my mind, so when she asked about my life, I fed her only trivial stuff; but stuff that could reasonably pass for being relevant to a therapist. For example, I talked to an excessive degree about the then-recent death of my grandmother. Her death was sad, of course, but it was far from the most pressing issue that was tormenting me. It seemed to be a pretty effective way of eating up sessions and getting the therapist off my back.
That's not to say that I never slipped up and gave the therapist more then I should've. Even talking about my grandmother once led into a fierce argument where I unwisely bared my personal values. But the strategy minimized harm, even if it wasn't foolproof.
I don't know what more help I can offer.
Be well, @Historylover .🙂