Mike my mother also suffered from dementia too. She was fine until she was in her early 90’s . Then she started forgetting things and asked me and my siblings why ? We reassured her cannot help it it’s part of the aging process . She was independent until the last year and a half of her life . She passed away 101 years and three months . Enjoy the last years of your mothers life and cherish it . Prayers to you and your family in this very difficult time .