Sorry to hear about your dog. There is no one here or at any other forum that can tell you the life expectancy of your dog because no one knows the circumstances or the severity. If your vet cannot answer your questions go to another vet. Please be compassionate and do what is best for her.
Also, you should not use an email address for a user name as there are bots that search the internet for these and exploit them with spam or worse. Best of luck with things.