In Part One of Fahrenheit 451, Mildred attempts suicide by taking an overdose of her sleeping pills. Her life is saved but, the next morning, she claims to have no recollection of the events of the night before. In fact, she tells Montag that she feels like she has a hangover. When Montag tells her that she took too many pills, she reacts with shock and denial:
"Oh, I wouldn't do that," she said, surprised.
Mildred is firm in her denial, despite Montag's repeated attempts to make her acknowledge and explain what she did:
"I didn't do that," she said. "Never in a billion years."
Mildred's denial of the overdose is representative of her personality, more generally. She buries her true feelings and instead devotes her daily life to the "family" and the parlour walls. Mildred is, therefore, symbolic of the dangers of oppression and censorship but her overdose suggests that entertainment has brought her nothing but misery.