Dear Tarpon,
First of all, I am so sorry that your dear mother has PD. My mother also had PD and I lost her early in 2010.
I am glad that you and your family are so very blessed to have Long Term Care which provides your mom 24/7 care and allows her to stay in her home. Unfortunately, we had no choice but to place my mom into a nursing home to provide skilled care 24/7 but she never stopped asking to go home.
I do not know if 2 years is a common time frame for your moms caregivers but speaking personally from being a caregiver to both of my parents for many years, I would not doubt that it would be common. Hopefully you will find a caregiver who will stay with your mom on a permanent basis so that she will not have to adjust to new people in her home. My best advice is to love your mother while you have her
Blessings!