Advice on long-term delirium please

Hi there, I hope if you’re reading this you’re well.

My grandmother is 93 and has gradually had an increasing degree of confusion about things, especially in the last 8 months. She recently was diagnosed with mild cognitive impairment but no dementia.
About 6 weeks ago the confusion got markedly worse. It was a few weeks later that she was given antibiotics for a UTI (which she frequently gets) and she has now been clear of the infection for nearly three weeks, however the confusion has only gotten progressively worse, and the doctors think it’s likely delirium.

She went into hospital last week for severe dehydration and not eating, came out after 24 hours and had to go back in less than 24 hours later. She came out a couple of days ago, having been on a drip to rehydrate her. The doctors seem to think the confusion/delirium is a result of the dehydration, though there’s still no improvement.

Aside from the obvious stress of all this, we’ve come upon some issues with how to manage the situation. The only family members that try to care for her are my mum and aunt - each living a few hundred miles away and both having a number of people reliant on them at home. They have managed remotely thus far to keep her living in her own flat, visiting every opportunity to sort things, and relying on her wonderful twice daily carers.

Now my gran refuses to drink (believing she has already had 3+ glasses of drink), and has become extremely unkind to my mum and aunt, to a point they can no longer try to correct the absurd/worrying delirium things she says (such as believing she’s a terrorist suspect) nor remind her to drink water. She has always bullied them to a degree but nothing like this. The lack of drinking will wind her up in hospital again before long.

My mum and aunt both have genetically inherited heart conditions and I fear will both wind up in hospital themselves if this level of stress keeps up.

My gran has outright refused any extra care or to look at care homes for years and continues to do so.

If anyone has any suggestions on how to manage this situation, or has any links to where we can find some practical/mental support for my mum and aunt, I would be most grateful. Thank you.

Given her age it’s quite difficult to expect her to change. Discuss moving etc. If only we could ask people with difficulties(trying to provide them with care) to us. To go along what we think is in their best interests.

How is she with medication? Would someone like a befriended be better than a carer. A befriended could gain trust and would be perhaps able to sign post where possible.