When I tell people that I've published books, they get excited and often share that they, too, have always wanted to write a book. So I like to encourage people to go ahead and just write whatever they feel led to write--whether or not you end up writing a book or whether or not you end up deciding to publish it, if it's the act of writing that you crave, then freely writing will still be a good thing either way.
It has never been such a common thing as it is now for anyone to write a book--because literacy has never been so high. It was really only in about the nineteenth century that literacy became widespread. So it has never been possible for so many people to write, and there never has been such a wide demand for content to read. But it has always been our instinct to write.
Before blogging and social media, before Lulu, before emails, we wrote letters and travel journals. Perhaps this is why I like pioneer journals so much. Formal letter-writing I associate more with the upper classes who could read and write before the masses could. But a person who had been to school for a couple years and had a copy of the Bible or a McGuffey Reader to practice with was capable of recording their own experience traveling across new terrain or setting up a homestead. They used paper to tell their own stories.
And that's what we were doing before literacy, too. Before we could write the words, we spoke them. You could tell your children a fairy tale or the family history. You could tell your neighbors about the time you got caught in a blizzard. You could tell your friends about how you met your spouse. We have always told stories.
So don't feel like only other people write books. Don't feel like you can't do what you would like to do. Don't feel like you have nothing new to add. There has never been another you. Maybe you will tell stories for millions. Maybe for thousands. Maybe hundreds. Maybe dozens. Maybe for one. Maybe just for yourself. But tell your stories, exercise your mind, and write what you want to write. Because it is a good and natural instinct to want to share your stories.