
One fascinating thing about both observing people and creating characters is the wide variety of ways that they can look at the world. Some people are realists, some pessimists, some hopelessly naive. These sort of differences become especially clear when obstacles are thrown in people's paths. Some crack under pressure; some become stoic and taciturn when confronted with grief. Others collapse in tears and guilt, while still others immediately start blaming the situation on everyone around them.
When writing your story, it's crucial to have a good understanding of how your character encounters obstacles and conflict. After all, your story, almost by necessity, will put your character under stress and throw a few curve balls at him. How will he react? Does he pretend that the obstacles don't exist, or blow them out of proportion? Does he run away, or rise to meet them? Try imagining how you would meet the kind of challenge you're throwing at your character. What would you do if you had to face a cheating spouse or financial ruin? Then think about the ways your character is different from you, and imagine how his or her reaction will differ. Keeping the character close to a real person in this way will ensure that you stay in touch with reality, with your finger on how real people react to challenges.
Make it your writing exercise this week. Write a few notes on how your character is likely to react to an obstacle you have in mind. Then try writing that scene where he or she meets it face to face.