Pride and Prejudice Volume 1, Chapter 20
Mrs. Bennet hurries to congratulate Collins, but he tells her that Elizabeth is being coy and refusing him for the moment. Mrs. Bennet tells him that Elizabeth is headstrong, but she'll make Elizabeth accept the proposal. Then realizing that Elizabeth's refusal was real, Collins begins to doubt that he wants to marry her. Mrs. Bennet tries to get Mr. Bennet to force Elizabeth to marry Mr. Collins. When Elizabeth tells her parents that she has refused Mr. Collins and will not marry him, Mrs. Bennet says that if Elizabeth doesn't marry him, she'll never speak to her again. Mr. Bennet then says, "An unhappy alternative is before you, Elizabeth. From this day you must be a stranger to one of your parents. --Your mother will never see you again if you do not marry Mr. Collins, and I will never see you again if you do." Volume 1, Chapter 20, pg. 78 Elizabeth is off the hook.
Charlotte comes over to visit and hears the news as Mrs. Bennet complains that her children and her husband are cruel to her. While the woman whines, Mr. Collins comes in and takes back his offer of marriage. He tells Mrs. Bennet that as much as he respects and likes the family, a marriage to Elizabeth wouldn't work out at all.