Though he said I could refer to him as "the loser who I could even FEEL the sobbing between the lines...", that's much too harsh. Therefore, he'll henceforth be known as my fellow writer (MFW).
He wanted to know why he knows so much about his character, yet:
...it feels like Jo sits with me in my room as I write but doesn't want to say a word to me...I suggested couples counseling to her but she just sits and stares at me...
And indeed, he provided some very specific, marvelous details about Jo.
So what gives? How can we know everything about our character, yet the character doesn't take flight?
Here's an answer via a partial of our exchange:
Me: What's Jo's defining detail?
MFW: OK Great question - Defining Detail - What is her Defining Detail? god, I think—
Me: Notice that phrase, "I think..." That tips you off that you don't yet know. The goal is to be so sure that if a random person tapped on your shoulder in the grocery store and demanded to know your character's defining detail, you could spit it out.
MFW: ...she is scared, but yet masked with this independence/courage/toughness—
Me: That's a start. But if you were in front of an audience of 100 people and said, "Okay all. How many of you are sometimes scared, yet hide your fear behind a tough exeterior?" how many hands would go up?
My guess is about 98.
The defining detail is meant to take your character out of that pool of general human emotions and instead point to that one millisecond of time when your character's thinking changed in a significant and permanent way. The kind of change that forever after affects — and predicts — what she does and why she does it.
The cool thing about defining details is that they are unique to that individual. No other person in this 6-billion+ world can claim to have experienced that very moment in that particular way.
So keep digging deeper until you see everything about that moment. It's the toughest task of character development. The good part is that from then on you'll know what the character will do in any given situation and why she'll do it.
The suggestion I'd like to throw out to MFW and everyone else is this:
Think of a single moment that changed you significantly. Write down everything you remember about the situation, including the time of day, day, date who was around, the reason you were there, whether there were any notable smells or sounds, etc. Write down what about that moment flipped the switch in your brain.
Did someone do or say something?
Did you see something that caused you to make a connection you'd never made before?
What did you start doing differently because of that moment?
If anyone would like to share a moment that defined you, I'd love to hear the how and why.
Thanks, MFW, for being such a great sport. We writers too often muddle around, not wanting to bother anyone, when what we should be doing is asking, learning, asking, learning.