What is a mothers role in her adult childrens life? I wonder if my mother plays that role.?

I do not feel that most people would understand me because my mother I believe is very mean towards me. I believe most people have a mother that shows care, love and support. I try hard to live up to the commandment, to love and respect my parents. How can this be accomplished when all my mother does is say mean things to me and puts me down consistently? She lives in my house because she cannot afford to live on her own. She contributes very little and says mean things to me such as: you are just like your father or grandmother, you are dirty, youo do nothing around the house, you are disrespectful, no one will marry you because they can't stand you, all you invested in your education was worth nothing, you think you are all that because you have a college degree, I will be at peace when I am away from you......these are among some things I hear from her. Yet although I am unemployed I pay nearly all the house bills, I am educated (mba and bachelors), fit, I don't do any drugs or abuse alcohol, I am actively seeking and going on interviews, I clean after her mess......it is difficult hearing all the means things she says. How can I respect my mother? The things she says are hurtful. If I speak about how I feel towards how she makes me feel, I feel like I am being disrecpectful towards her. That commandment is confusing because, How am I suppose to guard my heart as well from all this?