I think it's a different thing to resrict and direct what someone in her situation at that age may write about then a middle aged man. They are in very different places on the developmental wheel. There is no chance or point to trying to straighten this guy out. Not that he doesn't deserve therapy or anything like that.
If someone's journal writing seems to feed inapropriate behavior I think it may be acceptable to restrict it to whatever degree determined appropriate.
Every case must be considered some what individually and all the factors that brought them to the place they are at. And the first more important question for consideration is the age of the child or adult your are talking about.