We've had to in the past... It's never an easy decision, and it never will be.... If your dog is suffering, and in pain with not a lot of hope then the kindest thing you can do is set them free from their pain
It sounds harsh, but doing surgery can rack up thousands of dollars worth of bills on a chance of a maybe is hard to do.. Listen to what the vet says, and make a decision is all I can say.. I wish you the best in this trying time