I suspect the most difficult issue you are dealing with is the dementia. My father had dementia and he developed bladder cancer. He stubbornly refused treatment. As a family we made the decision not to force the issue even though we did not want him to die. It was a very difficult decision.

There is a cure for the aneurysm but there is no cure for the dementia.

Send you hugs and love in dealing with this very painful situation.