I love my mother the most and I am not that close to my father I also have a sister 20 years old she is a CP child who could not do her daily chores previously my mom use to clean her and feed her but now when my mother will die and my father has a very busy job that requires him to work almost all day 

I am also starting my carrer as a software engineer 
I for the fact know that of my mom dies my father would be in the worst possible position of his life 
the main and the most difficult thing would be my sister's daily chores I would not be able to see my father and my sister suffer at all I need to make a decision in life which I am not prepared to 
 I could not stop myself from crying alone at night every day is like a hole in my heart as I know the things my mother was doing for my sister I would not be able to do 

what to do I don't know we also don't live in a area where medical nurse would be available and with all the loans and expense of my mother's last 3 year treatment  we don't have any money left 

What should I do how to bring some positivity in my life