Sister is refusing to discuss distribution of estate - post probate

[Nickos]

My mum died at the beginning of the year, and probate was relatively easy to obtain despite her not leaving a will. Both myself and my sister were named as administrators of the estate. My sister still lives in my mums property and never really left home. Initially, I said that I would not rush her to leave the house, but that I needed to understand what she though her intentions would be in the long run. 9 months have passed and I'm still no closer to understanding what her intentions are. When I bring up the conversation, she goes silent and refuses to answer, only saying that she "hasn't thought about it yet" I try and reassure her that i'm not trying to get her to leave the home right away, but that I need to understand where I stand in regard to my share.

There is enough cash to enable her to buy me out, (at a loss to me, which I have offered to take this loss) if she wants to stay in the house. She refuses to tell me whether she wants to stay, or leave. I've equally offered my share of the cash to allow her to buy a smaller home which would be more appropriate, but she refuses to answer my questions.

I think there is a possibility that my sister may suffer from some kind of autism, though this was never diagnosed it has become particularly obvious since my mum died.

We only have each other left family wise, and so I don't want to ruin what is left with a legal challenge, but I'm at a loss as to what I should do next? Any advice or guidance from anyone who's been in a similar situation would be much appreciated.