But should it be your decision?

Yes, that is the question.
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Where do our responsibilities to her begin (and end)? I don't know.

It seemed to me the goalposts moved here. Do you really want to make the decision of where and how she lives? More importantly, do you really want to be responsible for the content of her last years - thinking you know best but finding out you don't?




But another question arises. Is it worth the strife in the household?

You're going to have strife regardless of what you do. And you're always going to second-guess whether or not you made the right decision. I would probably discourage her, but overall, I would guess that giving the support you can might be the best.




1poorlady is looking at flights for her (one-way...if she does this 1poorlady won't be bringing her back).

I can understand if finances wouldn't allow her return, but it reminds me of my mother saying "If you run away, you can't come home." Telling her that only inflames the situation (as opposed to easing the tension).