From Writers Helping Writers:
Debilitating fears are a problem for everyone, an unfortunate part of the human experience. Whether they’re a result of learned behavior as a child, are related to a mental illness, or stem from a past wounding event, these fears influence a character’s behaviors, habits, beliefs, and personality traits. The compulsion to avoid what they fear will drive characters away from certain people, events, and situations and hold them back in life.
In your story, this primary fear (or group of fears) will constantly challenge the goal the character is pursuing, tempting them to retreat, settle, and give up on what they want most. Because this fear must be addressed for them to achieve success, balance, and fulfillment, it plays a pivotal part in both character arc and the overall story.
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Agoraphobia is an anxiety disorder that causes people to be afraid of the places or situations that could bring on a panic attack. Their fear of being unable to get help or escape during one of these attacks can make it difficult for them to navigate open spaces, elevators, crowds, concerts, church services, movie theaters, or any place where a panic attack might come on. In extreme cases, a character suffering from agoraphobia may reach the point where they’re uncomfortable leaving their home at all.
What It Looks Like
Frequent panic attacks or elevated anxiety in certain places
Consistently avoiding certain locations or situations
Making choices that enable the character to stay at home (working from home, having groceries delivered, etc.)
The character often declining social invitations to certain places (amusements parks, church services, weddings, etc.)
Only venturing outside with a companion
Clinging to the friends or family members who are supportive
Common Internal Struggles
Wanting to not be limited by a fear but it being too strong to ignore
Knowing the fear is irrational but being being compelled to give in to it
Feeling guilty for making excuses about not being able to attend certain events
The character feeling like they can’t trust their own mind or emotions
Feeling defective or broken
Slipping into despair—believing that things will never change or get better
Wanting to seek help but feeling too overwhelmed or incapable
Feeling misunderstood and alone, as if the character is alone in their suffering
Worrying about what others think
Link to the rest at Writers Helping Writers