Actually its not unethical or against any therapy rules for a mental health person or any other profession to suggest writing a memoir. In fact most doctors, psychiatrists and therapists find keeping journals (memoirs, diaries, poetry, prose its called many things in many areas) to be quite healing and therapeutic. not just for mental disorders either. if you google just about any topic you can find a momoir by lots of people on what ever topic you google. last semester I had to do term papers on depression, breast cancer and Multiple Sclorosis. I found that many doctors and psychiatrists and therapists have included journaling, writing memoirs, poetry, prose as a huge part of their clients healing process.

I have also had 5 different therapists, medical doctors and psychiatrists, include journaling/writing memoirs as part of my treatment plans. a few of them even supplied the writing supplies and flash drives that they keep in stock specifically for the purpose of having their cleints do journaling/writing work.

A few of my therapists have helped me alot in documenting my extensive therapeutic journey because they had documentation to things that I didnt remember and because sometimes I was in altered states of mind so I was unaware of what was going on. the therapists documents supplied that information for me.

One thing to remember is that just because a therapist wants someone to write down their healing journey and history with the problem that they are seeing them for does not mean that journal/memoir is gonig to be published.