It depends. If the story is positive and your mom is okay with it, then it's probably fine. For example, if it's a story about how she overcame difficulties, it can be inspiring.
Well, it could be a story about a family trip to the lake. Maybe your mom looks really great in her swimsuit and is having a wonderful time by the lake, enjoying the sun and the water.
Her best friends could be the people she has known for a long time, like her old schoolmates. They share memories from their youth and have a deep bond.
Since I don't know the details, here's another possibility. It could be a story related to her hobbies. Perhaps she has a passion for gardening, and she transformed a small patch of land into a beautiful and flourishing garden. This not only brought beauty to the neighborhood but also became a place of relaxation and joy for the family. The story could detail how she learned about different plants, how she dealt with pests, and how she shared her love for gardening with others.
Your mom might be enjoying the peacefulness of the lake. She could be taking a walk along the lakeside, breathing in the fresh air and just being in the moment. It's a story about her finding tranquility at the lake.
One possible event could be that she moved to a new city and had to adapt to a whole new environment. She might have had to make new friends, find a new job, and get used to different cultural aspects of the new place.
This is completely unethical. Having sexual relations with a friend's mother violates many social and moral norms. It can cause great harm to the friendship, the family, and all parties involved. It shows a lack of respect for boundaries and relationships.