Yup duty, I think the key phrase is "doing their best". My upbringing was absorbed in drinking and cheating. It was far from their best. My mother had an affair and I got kicked out at 15.
I watched an Oprah show a very long time ago where she talked about giving up the wish. Giving up the wish can save you. I could sit an cry for the mother who wanted to be my mother, that woman does not exist. It would do me no good to continue to want. That sounds bitter. It isn't. I just think that the burden of change in the mother/daughter thing is there's to fix. Geeze, I can't imagine where my life would be if I were still lamenting over not having a motherly mother. Just because she is your mother doesn't make her exempt from nuturing that relationship. If having a loving and devoted, adoring daughter came to all those at a time they needed it for themselves, what honor comes to those mothers who sit up at night when you are sick, tell you are pretty, hug and kiss you? As has beeen said here many times, trust is earned. I think in many ways our cold relationships with our mothers does resemble our relationships with our alcoholics. They want the rewards without having made any investment.
It's OK to not like your mother. If you were to make a list of the loving things in life that are free to give, what did she give?