How can I stop my patient from constantly biting herself and constantly putting her fingers in her mouth and wiping her saliva?

She's 56? Wow. That's a horrible situation for someone so young. I think the above suggestions sound helpful.

Along with what sjplegacy said, you can also perhaps have her wear some gloves or mittens on her hands and see if that might help.

Her behavior may be a sign of anxiety. She may not even be aware of it. Try getting her something that will keep her fingers busy. An activity apron, worry beads, something to fold or organize. Mention this behavior to her doctor.