I don't think memoir subjects can really grasp how fully they are with you when you are attempting to channel a book-length work on their behalf. Every day for the better part of a year, you sit in front of a screen and try to conjure their reality, their words, how they might have experienced the events of their lives through their five senses, even beyond what they have yet been able to share. So much connective material must be inferred, and you hope that when they read what you give them, they will exhale and say, yes, you got it right, and if you didn't get it right, they will say, no, not quite, it was like this, because what you managed to put on the page has helped them call to the fore memories that had been in hiding before, and oh, it's an incredibly intimate dance, and the sustaining of it requires a kind of attention and devotion to both person and craft that is hard to describe. But I'm in it, now. I'm in the middle of the great sea and stroking through the water slowly, thoughtfully, intentionally—rowing faithfully for shore.
A dismaying yet absolutely predictable feature of this process is when you look at what you have written and it all sounds like drivel. Maybe you just need to sit in a different boat for a while, take in a slightly different view, because even in those moments, you must press on.
Arriving at forty thousand words this morning, I'm halfway to a completed first draft. After that, the process gets a little easier, as you now have a map you can pore over with your subject in the effort to discover where refinements must be made.