This is a cute saying but very true. One can't dwell on the past, everyone is human and can make mistakes. It takes a special and strong heart to accept that, and to Forgive and let go. But do it for your own sake too because it feels good to be happy!
Narcissistic grandparents love to steal your children from you. Sometimes physically steal them, but most often steal their hearts. She will slander you to your own children behind your back. She will create anarchy against.
I was so sad for my husband when he saw his mother in her true form, as she is, for the first time: an abusive, narcissistic controller. He has devoted himself to protecting our children from her ugliness.