This is actually rather a famous quote that comes as the final sentence of Chapter 1 of this classic novel. In it, Austen as the omniscient narrator tells us all there is to know about Mrs. Bennet, Lizzie's mother. Note how the sentences before pad out this description:
Her mind was less difficult to develop. She was a woman of mean understanding, little information, and uncertain temper. When she was discontented she fancied herself nervous. The business of her life was to get her daughters married; its solace was visiting and news.
Note how the description sums up her character in a very blunt and not at all flattering way. Mrs. Bennet, unlike other characters such as her husband, Mr. Bennet, is profoundly limited in terms of her life's purpose to marrying off her daughters and then visiting others and gossip. That is the extent of her life. In this sentence then Austen persents us with a satire of many married women with daughters of her time, whose focus was trying to secure an eligible match for their children.