I like writing, I enjoy writing, but writing fictional stories.... I don't really think it's inherently therapeutic for me. Especially, since I have trouble with my ability to focus, and that hinders my writing, all the while my mind keeps getting flooded with ideas.
If we're talking about writing in general, however, it can be. Writing down things I'm grateful of, or generally things that happened in one day like a diary, definitely has been quite therapeutic for me. Whether it was a bad day or a good day, I love writing down what happened or what I did for the day. I like looking back at my diary, recalling what good things happened the past few weeks, few months. Definitely kinda therapeutic.