Rarely do we find stigma discussed in a novel– although there are notable exceptions.
But blacks, Hispanics, gay men and lesbians, disabled, mentally ill, older people, the poor, and artists are all, to an extent, on the fringes of society.
As someone who fits into several of those categories, I realize how counter-culture my life is: I have never owned a house, I can’t afford a car, I rarely vacation. I am single. But I am protected because I am in several social groups, have lots of friends and rewarding work.
My novel is about a gay ballet dancer. He has two strikes against him and yet I have no included stigma in his story.
And I have never reflected on the stigma in my own life.
To make the story life-like I need to reflect on the stigma in my character’s lives and my own.
One last thought: this is a highly alienated culture. It is entirely possible that nearly everyone feels stigmatized.