No, it is completely inappropriate. Such topics are private and inappropriate to share with a parent, especially a mother. It violates social and family norms of propriety.
Definitely not normal. In a healthy family relationship, there is respect for personal privacy. Her behavior crosses the line of normal parental - child interactions. You need to take steps to stop this behavior as soon as possible.
Definitely not. This is a very abnormal and inappropriate situation. Family relationships are based on respect and propriety, and this kind of behavior violates basic family values and can cause great harm to family members both psychologically and in terms of family harmony.
There are many great kids' stories. For example, 'The Little Prince' is a wonderful story about a little prince traveling through different planets and learning about friendship, love, and the meaning of life. It has beautiful illustrations and deep philosophical ideas that are presented in a simple and engaging way for children.
Maybe she just doesn't have the knack for it. Some people are not good at being creative or engaging when it comes to storytelling. She might not be used to telling stories to others, especially for the purpose of helping someone sleep.
Adventure stories are great. For example, stories about exploring ancient ruins, like Indiana Jones - style adventures where the hero overcomes various traps and enemies to find hidden treasures.