How does Helen Fielding use imagery in Bridget Jones's Diary?

Examples of Imagery:

"As women glide from their twenties to thirties, Shazzer argues, the balance of power subtly shifts. Even the most outrageous minxes lose their nerve, wrestling with the first twinges of existential angst: fears of dying alone and being found three weeks later half-eaten by an Alsatian."

"Lately, therefore, whenever things have risked raging out of control, I have repeated the phrase "inner poise" and imagined myself wearing white linen and sitting at a table with flowers on it. Inner poise."