(((((((((((((((ohseedee)))))))))))))))))
I think it is a coping skill. My daughter has stories running through her head all the time. For her, it's part of OCD and a way her brain has figured out to cope with life. The more stress she is under, the more stories her brain writes.

It helps her to write them down and in fact has become an excellent writer through it all.

For her, it is different than dissociation, although she does dissociate to a small degree. Good luck as you figure things out.