I'm sorry, your mother seems a nightmare.
The good news is that the house is in your name. Don't sell it while your mother is alive - it's yours, and you need it towards your pension. Sounds like selling it will lead to your mother feeling entitled to the capital, which isn't fair, as many others who are capable of doing maths have pointed out.
I'd recommend as others say you go over, get the locks changed, and sort out rental one way or another. If you get a good estate agent they can organise things like renovations, painting, buying up to date furniture to get market rate rent. Yes, there will be a bit of a premium on this, but in my experience not huge and certainly worth it for someone else taking care of the hassle.
I would keep the rent and put it towards your own living expenses or salt it away in a pension.
There will be no way you can win with your mother on this, so I wouldn't bother trying. If you like, you can give her half the rental after management fees and once all updates have been paid for. But I wouldn't bother.
You can point out how she has reaped more than her fair share and clearly the arrangement is no longer working.
Good luck whatever you decide to do!