I can't say what I would do if I were you, but if I were me, and my cat was in that postition, then it would be time to be thinking about a new cat.
I've got two cats now, and have had as many as 8 at one time, and am crazy about them. The vet said Norman will die without the surgury. Here's the bad news: He will die anyway, maybe later, maybe sooner even with the surgury.
You do not buy eternity with the $1800. You don't even get a 90-day guarantee. A new cat, spayed or neutered and with shots from the pound is about $50. A gucci one from a pet store is a couple hundred. Get the $50 alley cat from the pound. They are sweet, tough, durable, and very happy for you to save them from euthanasia, and generally have a better long term outlook than poor Norman, bless his heart.
VERY TRUE!!
Excellent points bump.