There are many ways to get from A to B, so here is another entry from someone that seeks to find passion and fulfillment.
There are multiple facets to why I find creative writing mentally and emotionally fulfilling. Over the years that I have written short stories and my novel, I have turned over my motivations inside my head, and like a crystal held to the sunlight, I have learned much about creative writing and myself by carefully examining each individual facet for all their flaws and beauties.
Among my motivations, perhaps the simplest to understand is my creative expression and the exploration of the imagination. Each time I write, I plunge deep within my own mind and discover buried reservoirs of ideas. Now tapped, these ideas bubble up to the surface eager to see the light of day, and each time I express these ideas, I feel relief at the release. This exploration of my imagination and the expressing myself fills me with a great sense of personal satisfaction, which increases when I am able to share my writings with friends, family, and anyone else willing to read and listen.
Writing for an audience can be emotionally fulfilling in its own right. While I believe that writing is, first and foremost, an act to nurture oneself to learn and develop as a person, writing for other people can be a prime motivator to continue writing even when you've run out of steam. Perhaps it is arrogant to think so, but I enjoy writing to a wide audience with the hope that they will benefit from my stories. Whether great or small, words have the potential to influence and change people for the better, if they are willing to change. Whenever I write stories, I write stories that I personally find entertaining, engaging, and meaningful, and while I do not write stories to create high art or great literature, I do hope other people might find something of value from my work.
Of course, my stories wouldn't even exist if I knew nothing about people, the world, and myself. When I wrote my first stories, they were short and simple things, often based directly from my real life experiences, which as a pre-adolescent were few. As I grew older and learned more, however, my stories grew in depth and complexity. I found that to avoid dry, repetitive, and trite stories, I needed to ever increase my knowledge about writing, the world, and people. This challenges me mentally, and while creative and critical research aren't conventionally entertaining, they can broaden one's knowledge and their worldview. You never know, you might just find a new favorite interest or hobby out of it as well.
In fact, I have recently discovered a new interest from creative writing: self-therapy. While not conventionally therapeutic, creative writing helps me cope with my personal problems by encouraging introspection into a wide variety of topics. When I brainstorm my stories, I am regularly required to examine my beliefs, morals, and ideals as to why I think certain story elements are of worthy merit to write about. For example, I might ponder why I value self-sacrifice enough to include it as an important plot point or theme in a story, and whether self-sacrifice is an action I should promote or critique in a story. This would also encourage me to look for second and third opinions on such a topic. Depending on my conclusions, I can learn more about my values, why I believe them, and what they mean to me rather than simply taking them at face value.
These facets are the main reasons that I find creative writing fulfilling. I do not presume that every writer and artist feels the same; I am sure there are quite a number of people who create for entirely different reasons and who find creative writing mentally and emotionally fulfilling in other ways. Even the reader may find their own unique reason why creative writing fulfills them, and if so, great! That simply fills the world and its people with greater diversity, and if so, then I strongly encourage everyone to write their own stories, if only a sentence and a word at a time.