How do Stella, Blanche, and Stanley show denial?

At the play's conclusion, Stella shows denial when she makes herself believe that Stanley is trustworhy..... that he did not rape her sister.

STELLA: I couldn't believe her story and go on living with Stanley.

Over the course of the play, Blanche goes from purposeful liar to a world of unreality. She believes her own lies. This is apparent in her insistence that Shep Huntleigh is pursuing her.

STELLA: I--just told her that--we'd made arrangements for her to rest in the country. She's got it mixed in her mind with Shep Huntleigh.