What does Mildred reveal about society?

In Fahrenheit 451, Bradbury uses the character of Mildred to make some important points about the nature of the book's society. 

Firstly, Mildred's addiction to technology reveals the dangers of censorship and government control. Mildred is so dependent on the Seashell radio, for example, that she has become an "expert at lip-reading" and cannot sleep without its presence. This addiction has turned Mildred into an empty shell: she rarely expresses feelings and prefers to immerse herself in the world of the parlour walls.

In addition, Mildred does not make any emotional connection with the people around her, not even her own husband, Montag. She cannot remember, for instance, how she met her husband. Furthermore, the conversations she has with Mrs Phelps and Mrs Bowles reflect the nature of her friendships: they are shallow and based purely on a mutual love of television. 

But Mildred's true significance in the book lies in her unhappiness. Her suicide attempt, for example, reveals the extent of Mildred's misery and the fact that she denies it to Montag shows that she is unable to face her demons. Ultimately, Bradbury uses Mildred to show that a dependence on technology and the pursuit of mindless entertainment will never make a person happy. We see this most clearly in Mildred's imagined, yet incredibly violent, death:

It was such a wildly empty face...she recognized it as her own and looked quickly up at the ceiling as it and the entire structure of the hotel blasted down upon her.