12 isn't that old for a cat. I had one live up until 16. Belle is only 5. I got her when she was 10 months old. By that time the poor thing already had emotional issues that still show sometimes. She was taken from her mother too soon as a kitten and then placed in a home with multiple adult cats (not a good situation!), then when she wouldn't warm up her former owners hauled her out from wherever she was, which is counterproductive. Finally they took her back to the shelter, where she was placed into another room with all adult cats before they finally took her to Petsmart where she had her own enclosure and my mom and I adopted her. When we knew we were getting a cat, while we figured while we'd get a sweet one, we'd get one that we'd have to work with because those are the hardest cats to adopt out but they become your best friend.
Anastasia...what a name for a cat. You could get another and name her Drizella...