A bisexual character is shown as mentally unstable or struggles with addiction, especially when this aspect of their character is associated with or parallel to the character exploring their sexuality. The trope applies when bisexual characters are portrayed as having unstable behavior and relationships, or are “damaged”. Historically, LGBT+ characters have not been allowed happy endings. Once mandated by the broadcasting standards Hayes Code, “deviant” characters (including all LGBT+ characters) must not be made sympathetic or rewarded, and narrative punishment for this behavior remains pervasive even now that mainstream attitudes and laws have changed.
Though the understanding of mental health issues in society has progressed and people who struggle are no longer always stigmatized as “crazy” or dangerous, the portrayal of these issues in fiction lags behind. In the Unstable Bisexual trope, same-sex relationships or behavior are tied to the abuse of drugs and alcohol or are symptomatic of a mental breakdown, further linking the character’s orientation to their “unhealthy” behavior or mental illness.