Another issue is that due to the whole backlash of False Memory Syndrome, many therapists will not do hypnotherapy to retrieve memories. My T also does hypnotherapy, but won't do it with me because I/we react badly to it (from being through something similar in the abuse).
There's a whole safety issue with therapists "telling you" what your memories are. They can guide you to "hear" the others, or find ways to communicate (art, write, collage), but Therapists can get sued by family members or even clients if they deal with memories that then "might be false". It's a sticky issue, but one they're pretty careful about.

I did mostly journaling, and also non-dominant hand writing. So, for me, writing and drawing with the left hand (as suggested in the book about non-dominant writing) goes around the censoring mechanism in you brain -- but ONLY if your parts feel it is safe enough to tell you.
Wishing you the best.