Moll suddenly finds herself a wealthy widow (she has saved 1200 pounds of the money her first lover gave her), alone in London, and "still Young and Handsome." She is courted by several men before she marries a draper, a tradesman who strikes her as being "something of a Gentleman too." His extravagant expenditures soon cast them into poverty, however. He is arrested and then escapes from prison and flees to France. This leaves Moll in a strange predicament: "I found I could hardly muster up 500 l. and my condition was very odd, for tho' I had no Child,...yet I was a Widow bewitched, I had a Husband, and no Husband, and I could not pretend to Marry again, tho' I knew well enough my Husband would never see England any more." She decides, accordingly, to dress as a widow and begin a new life under the assumed name "Mrs. Flanders." She soon finds herself among a miserable, "wicked" company of men and does not feel inclined to return any of their attentions.
Moll reflects on the extreme disadvantage women are at in the marriage market. Her own situation is such that it "made the offer of a good Husband the most necessary Thing in the World to me," but the people with whom she is acquainted all know that she has no fortune, a handicap over which "Being well Bred, Handsome, Witty, Modest and agreeable" cannot prevail. Moll gets help from an acquaintance, who carries her into the country where, together, they cultivate the public misinformation that Moll has a fortune of 1500 pounds. Moll then finds herself courted by a plantation owner and, during a flirtatious game, tricks him into saying that he would marry her even if she were penniless. Once they are married, he bears the news that she is actually poor with relative equanimity, stating "that indeed he thought it had been more, but that if it had been less he did not repent his bargain; only that he should not be able to maintain me so well as he intended." In light of their reduced prospects, he expresses the wish to move to Virginia, where his plantations are, and where his mother and sister live. Moll agrees.
The whole family is getting along well in America, and Moll "thought myself the happiest creature alive; when an odd and surprizing Event put an end to all that Felicity in a moment, and rendered my Condition the most uncomfortable, if not the most miserable, in the World." While her new mother-in-law is telling some stories, Moll suddenly realizes that the woman is actually her own mother by birth, and that she has inadvertently married her half-brother. Appalled in this moment of recognition, she hesitates to reveal her discovery to her husband; she knows only that she cannot continue in the marriage. She insists on being allowed to return to England--without giving a real reason--and her husband refuses. They quarrel regularly and begin to be on very bad terms. Finally Moll confides in her mother-in-law/mother, who recommends that she "bury the whole thing entirely" and continue to live as before. She also promises to provide for Moll in her will. Moll is too disgusted at the thought of "lying with my own brother" even to consider this option. She finally tells her husband/brother the whole story, and the news throws him "into a long lingering Consumption." Moll once again demands to go to England, and he is in no condition to resist. After eight years in America she sails for home, and she and her husband consider their marriage effectively dissolved.
The disappearance of Moll's second husband to France is the first of several occasions when Moll will find herself with "a Husband, and no Husband." Her solution to this problem is to close the door on her past and assume a new identity. She embraces the same strategy for dealing with her incestuous marriage, and she will continue the practice throughout her life, becoming increasingly adept at molding her disguises and personas to her own advantage.
Defoe depicts, through his heroine, the harsh realities of the marriage market. He himself was outspoken in his criticism of the practice of marrying without love, calling such alliances "legalized prostitution." This candid and unsentimental presentation of the economic motives governing marriage casts Moll's frankness about her own motivations in a new light. If we were inclined to see her avowed acquisitiveness as overly mercenary, we are now forced to acknowledge, at the very least, that she is a creature of her world.
Moll's moral disgust at the revelation that she has been living with her brother as a husband is somewhat surprising, given the equanimity and lack of emotion with which she has met the other tragedies that have befallen her. This is one of the rare cases when a moral principle will outweigh every other consideration for Moll. Even in this case, however, her initial repulsion is quickly channeled into a more pragmatic vein as she calmly considers what action she ought to take. The news causes Moll's brother/husband to suffer a breakdown, a fact which reinforces, by contrast, Moll's personal resourcefulness and resiliency.
This episode serves as a link between the beginning of the novel and the end: it shows Moll rediscovering her mother and her own origins and also paves the way for her return to America and her final attainment of prosperity.