You have my support, I went through this 2 years ago, with Sassy. She was 10, we did everything we could for the arthritis but it stopped helping, acupuncture, medication...nothing worked after a year. It was the hardest thing I ever had to go through. She peed in her cage everyday until the end, and I could tell she was embarrased and absolutely miserable. "the decision" was probably the most selfless thing I've ever done.

If she still seems happy, then you're fine for now. She's getting older, her joints probably get a little stiff. I would discuss all this including arthritis, piddling, etc. with your vet. Even if arthritis is not in the picture, it seems her joints are a little stiff. I am sure he can give you some ideas on how to help her. I took Sassy for alot of walks going through this time and it did help quite a bit. Don't start thinking about when it will be her time yet, whenever it is you will know, trust me.

Just live in the moment and enjoy the time you have left with her.