Will I follow her down the dementia road?

I am the caregiver of my mom.  I have siblings but they don't live close, so decisions and care are left up to me with the help of my husband.   After my dad died in 2002, she continued to live at her home alone.  In 2005 she suffered a bowel obstruction and required two surgeries and a month of rehab.  We noticed changes in her mental condition after that experience.  Several times we hired caregivers to come and stay with her so she could stay at home, but she would run them off almost as quickly as we hired them.  We brought meals in, but she fed them to her little dog.  We divided her medicine into little compartments, but still she would forget to take the pills.  In 2007 her little obese dog died, probably from all those extra meals. No food, no medicine, no pet, we began to worry even more.  Early in 2008 we moved her into an assisted living facility.  She's eating meals and taking her medicine, but her mental condition continues to diminish.  We know that her father and his sister both suffered from dementia.  Will I follow my mother down that dementia road?