There is an interesting novel, very well done, published in 2002, I think, called Moral Hazard by Kate Jennings, then a woman in her forties living in New York whose somewhat older husband had died of Alzheimer's. Her central character is ... you guessed it.
The central character, who is an artist, has to go to work in a financial firm in NYC in order to pay for the catastrophe that has befallen the couple. She clearly loves her husband dearly. She has to repress a lot, really a lot, to go to work -- you can feel the teeth gritting more and more each day -- and yet she does, and she writes interestingly of life at the heart of USian capitalism.
Guess where the firm she works for is located.
Late in the novel, central character gets a doctor's name and address and makes a visit, and a quiet transaction is made. And then she does the deed.
It is a very disquieting novel. It leaves you wondering about many things. It was courageous to publish it, I think. I don't know how far it has gone in the culture -- it was reviewed in the NYT when it first appeared.