Blanche proves that "it's not just a river in Egypt." She does live in a state of denial about many things. The first and most pressing level of disconnect in her own consciousness is that she is unable to fully grasp that the world in which she matured and understood as being the bedrock of reality, the traditional South, has given way to a new and more cosmopolitan notion of the good. These values which were so embedded in this world are no longer present in this new setting. Blanche has a difficult time balancing this disconnect, this divergence. Rather than accept the fact that what was once is no more, Blanche believes to a great extent that through sheer will and subjectivity, it will return. Similarly, Blanche has not fully processed her own mistakes and failures in the realm of the personal. She hints at it such as "riding the streetcar" and other insinuations that indicate that what was done in the past should not have been, but there is not a moment in her consciousness, at least to the reader/ viewer, where she fully accepts her role in making these mistakes and learning from them. Blanche's refusal to do so helps her advance in her own denial, but also in her inability to interact in a stable manner with the world. We joke about the "river in Egypt" element to Blanche, but Williams might be constructing a character that compels us to fully grasp the dangerous implications of denial. I encourage you to examine this more in the play by finding moments where Blanche demonstrates an inability to cope or understand the world in which she lives. This is an element of denial being explored in the play.