It made me feel happy to read it. I must have read it every day for two or three weeks, because it made me smile when I felt like crying all the time. She served me with that story. (I also got through with a ton of help from the incomparable Suzette, but that's another story.)
Do I serve others when I write? Yes, I do. Some things I've written are really obvious acts of service: girls camp skits, Boy Scout programs, puppet shows, Primary programs (lots of those), letters to the editor. I once wrote a short story especially for my Mom to read to the teenage girls at church. But if something that I've written has touched someone else in some way, then yes, it was an act of service. No need to feel guilty about doing that. Of course, in order for writing to become an act of service, you have to actually share it. So, get out there and share it!