Imagine doing all the emotional/psychological work to process things you've been through, building healthy coping mechanisms and become self aware enough to make progress only to have a reset button that wipes that progress with amnesia walls and you have to figure out increasingly more succinct (but intense) ways to get through that process without knowing thats what you're doing in order to process it again... THAT is the hardest part of DiD and why we make music, art and write.
5 steps forward, then take those 5 steps again, then a 6th step, then those 6 steps again...Only realising after taking them that you'd been there before. Like a constant state of dejavu and uncanny valley with your own experiences. Its a trip at the best of times.