I am so sorry to hear that you are having this discussion and thinking about these decisions at this time of year! It is never easy, and even though I have worked with many folks over the last 10 years about these decisions, it does not get any easier!
I am a little surprised that she is having these problems at 6 years old. Am I reading that correctly?
Quality of life is so very important for all of us. I tell my clients that when their pet is not doing the sorts of things that they did before, and not enjoying life, it is time to be thinking about euthanasia.
Having said that, the problems that you are describing are manageable. There are many dogs in the world who are deaf and blind who do well. It is very important that you don't move things around much in the house.
The hip problems can be more difficult to manage, particularly if she did not improve after the medications that your veterinarian gave you. We can have a discussion about medication options if you would like.
Ultimately, you have to make this decision as a family. If you feel that her quality of life has diminished significantly, it is certainly acceptable to pursue euthanasia. Regardless of what you decide, I would support your decision.
Please know that you can ask me further questions and discuss this further using the "Reply" button, and I am happy to respond as many times as it takes for you to be comfortable with answers.
Again, I am so sorry that you are facing this at any time, but particularly over the holidays.