William Styron chronicles his battles with serious depression in Darkness Visible.  He feels marginalized because his illness claims him and keeps him prisoner, even when he is in places where he should feel joyous. He writes the following about feeling depressed when he is going to Paris to claim a literary award: "My dank joylessness was therefore all the more ironic because I had flown on a rushed four-day trip to Paris in order to accept an award which should have sparklingly restored my ego." This type of depression, which sets in when he should, according to rational thought, feel happy, isolates him from others. He writes of depression, "It thus remains nearly incomprehensible to those who have not experienced it in its extreme mode." In other words, his mental illness makes him feel marginalized because people who haven't experienced it directly can't understand it. 

Even when Styron has companionship, he feels utterly alone and senses a feeling of alienation. He writes:

"The sufferer from depression...finds himself, like a walking casualty of war, thrust into the most intolerable social and family situations. There he must, despite the anguish devouring his brain, present a face approximating the one that is associated with ordinary events and companionship.... But it is a fierce trial attempting to speak a few simple words."

Styron feels unable to connect with those around him as depression causes him to feel anguish, but he must force himself to go through the mundane interactions and details of everyday life when his mind can't concentrate on them. Even though he is surrounded by other people, he can't connect with them, causing him to feel marginalized because he has to pretend that he isn't suffering. 

Dr. David Welton, author of The Treatment of Bipolar Disorder in Pastoral Counseling, believes that the church should play a role in helping people who suffer from mental health disorders, such as depression and bipolar disorder. Dr. Welton believes that the church can create a sense of community for people with mental illnesses and make them feel welcome. This sense of community can provide them with fulfillment that makes them more hopeful and less despairing. 

One way William experiences marginalization is through the isolation the illness of depression throws him into. As William loses interest in more and more parts of his personal and family life, he withdraws more and more and becomes more and more marginalized as an "other" because of the improbable behaviors his illness forces his family and friends to witness and be confused by.