I was five when my parents divorced. My father was an alcoholic. My mother told me the truth and explained things to me. She spoke with respect of him as a man she loved and a father who loved me and then explained the however and but. Also, I always viewed her as doing me a favor. My sisters were the result of an alcoholic parent, 12 and 14 years older then me, as they had to grow up with my father. It was more like I was a child of an only parent.
One of my sisters is an addicted. So my mother had to tell me the truth about her. Such information also served to protect me when I was with either of them. I raised my sisters daughter for many years. I shared the truth with both my niece and my kids at a young age. This also served to protect them.