I love this concept of imaginative nurturing! It's so true that our brains can't tell the difference between real and imagined experiences, so we can use our stories to give ourselves the kind of support and love that we may not have received in real life.
I've found that imaginative nurturing can be especially helpful for people who have experienced trauma or abuse. By writing stories in which your characters are supported, believed, and loved, you can start to retrain your brain to expect these things for yourself.