According to Rich compulsory heterosexuality means that we are obligated to be heterosexual. That society trains us to be this way and only this way. It is only okay to be heterosexual in our society, and Rich explains how lesbians are not equal to straight people. Rich explains how lesbians often have to hide their orientation so they aren't discriminated against in the workplace. She even states that lesbians have been fired from their jobs, and that they are even fired from institutions that were created by feminists. She also shares how feminist literature is mainly heterosexual, and does not mention lesbians.
Rich explains lesbian existence by saying how lesbians don't really exist in society. She talks about how there is never any mention about lesbians, in society or in literature. Rich mentions how there is "a scale ranging from deviant to abhorrent or simply rendered invisible", to describe lesbians. She continues to explain this through many articles and books that she has read, and it gets more confusing.