To use myself as an example:
I am a human, a wife, an ex-wife, a step-wife, a parent, a child, an artist, a game person, a shy person, a leader in some circumstances, a brave person, a frightened person. I am kind-hearted and mean. I am honest and sneaky, law-abiding and rebellious.
But that's not enough to be interesting. The interesting thing is the loyalties and conflicts in loyalties, the goals and conflicts between goals. I am a wife. I have a partner to whom I'm responsible and for whom I'm responsible. But I'm an ex-wife and co-parent -- and sometimes co-parent goals and wife goals can seem or actually BE in conflict. My ex's wife is my friend, and I have responsibilities -- as a friend -- to her. Her children are not my children, but they are in my family and I love them. What if Christopher's needs conflict with mine or Curie's or John's or Daniel's? It's not as easy as saying, well, one's spouse's needs come before one's ex's stepchildren's needs, because needs are not equivalent. What if John needs soup and Christopher needs a kidney? Okay, so those are all "easy". What if John needs soup and Christopher needs a walk with me to talk about something? What if Greg is antsy about Em missing school next week and John and I reaaaaallly don't want to travel after Sunday?
It's a juggling act, and it is always a juggling act for any human who has a relationship with more than one person.
That's what characterization is, to me. A novel can't encompass all of a character's relationships, any more than it can cover every single action of the character's day. But it doesn't need to. I have to pick the important relationships, the important conflicts, and make those choices the driving forces in the novel. They certainly are in real life.
