I take care of my father without pay, is this considered being employed by someone?

My mother and siblings work while I take care of my disabled father. I am sometimes critized for not having a life and I wonder at why this is. I have to bathe my father, help him around the house, cook for him, watch over him, keep the house clean and a variety of other things. I am asked to do this by two other people who live in the house. Is this considered a job or work? My dad was rendered disabled two years ago. He is somewhat of a man-child and very dependent upon me.

What does this make me? What is the proper word? My dad does not like the word babysitter. I guess I prefer the word caretaker over nurse. Would the reader consider this a job, work and an employment? I am just curious.