Memoir and truth

OPINION — When I hear a book is a memoir, I have learned the hard way, that it doesn't mean what the author wrote is true. Memory itself is not trustworthy. Ask most two people who have divorced and you will typically get two narratives of their former marriage that cannot be reconciled. Yet, usually, neither are lying.
I remember the episode of Nova called The Memory Hackers. It is our nature, it seems, to adjust our memory based on the environment we are in at the time we are remembering. It also seems every time we remember something the memory itself gets altered.
Sometimes, an author's failure to be true to actual events in a memoir seems intentionally duplicitous. For example Lance Armstrong's book It's Not about the Bike: My Journey Back to Life, which failed to mention that he was cheating when he won the Tour De France many times. Yet, the book inspired me at the time to be a stronger cyclist.
I have read this and other books in the category of memoir, only to later learn that the author's telling of the story did not match up with facts, the author didn't remember correctly, greatly embellished the story, misrepresented themself and/or made the story up.
In the end does it matter? Stories create a vision of the possible. The narrative may not be true, but if it sparks the imagination, maybe entertains, maybe improves the reader's life, is that what matters most?
I had a girlfriend once that was an amazing storyteller. I used to say of Kathy, "she never lets the truth get in the way of a good story." I never took her stories literally. She's gone now but I remember her fondly. Was she lying? I will never know. But, I still remember her stories joyfully.
So, when I read a story that's labeled memoir, I think, "fiction; maybe kinda based on a true story." The author, like Lance Armstrong, may be later labeled a liar and/or a jerk. But, the story. The story has its own legs and, if it sparks something inside you and I, the readers, we can take that and create our own stories, our own truths.