I was sexually abused by my father as a child. It went on for a number of years and deep down I'm sure my mum knew something was up. I eventually went to school (and then the police) when I was 16. I started experimenting with a bf and realised what had been happening at home was wrong.
My mum said she didn't know although acknowledged that I was my Fathers 'favourite' 
He went to prison for 10 years and I stayed at home with mum + 3 brothers.
She's been a mess since then and struggled with mental health on and off. Just about scrapes by now. My brothers all feel sorry for her and say how tough it was on her (what about me!)
I feel petty because although I got into an abusive relationship in my 20s I've done really well since, have a great career, wonderful husband and we are financially stable, something my mum never managed.
I have momentary flashes though of intense anger, either for knowing what was going on and throwing me to the wolves or being too dense/thick/ in denial to see.
I'm mid 30s now so not sure it will ever go away, I wish I could be as serene/forgiving in the inside as I pretend to be on the outside 