Why does my mother-in-law refuse to walk even with help?

Hi doctor,

My mother-in-law is 93 years old and had her hip replacement done for five years. She could walk after that, but we have kept a lady to be with her for twenty four hours a day and 365 days a year after the operation. She does not have diabetes or has any heart condition. She takes one tablet of Neurogen, Glutamine Plus, Seven Seas capsule, and 75 mg of Ecosprin. Recently, she has started swinging her neck from side to side when seated crouching forward. Also, she is complaining of body pain and refuses to walk even with help. When walking held by the lady, she suddenly tries to sit down. I appreciate any advice to make her life comfortable.