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Mormonismo e Poligamia/Divórcio no século 19
Tópicos do Evangelho: "O divórcio estava, portanto, disponível para as mulheres que eram infelizes no casamento"
"O Casamento Plural e as Famílias Polígamas nos Primórdios de Utah," Tópicos do Evangelho em LDS.org:
Os líderes da Igreja reconheceram que o casamento plural podia ser particularmente difícil para as mulheres. O divórcio estava, portanto, disponível para as mulheres que eram infelizes no casamento; um novo casamento também estava prontamente disponibilizado.
Question: How were divorces formalized among Mormons on the frontier in the 19th century?
Some members of the Church remarried without obtaining a formal legal divorce
Some members of the Church remarried without obtaining a formal legal divorce. Was this adultery? Remarriage without a formal, legal divorce was the norm for the period, especially on the frontier and among the poor. These were the legal realities faced by nineteenth century Americans.
"Presentism" is an analytical fallacy in which past behavior is evaluated by modern standards or mores. Even worse than a historian's presentism is a historian exploiting the presentism of his readers. Critics do this repeatedly when they speak about legal issues. "Presentism," observed American Historical Association president Lynn Hunt, "at its worst, encourages a kind of moral complacency and self-congratulation. Interpreting the past in terms of present concerns usually leads us to find ourselves morally superior. . . . Our forbears constantly fail to measure up to our present-day standards." 
To remarry without a formal divorce was not an unusual thing in antebellum America
Louisa Rising married Edwin Woolley "without first divorcing her legal husband," the dust jacket of George D. Smith's Nauvoo Polygamy teases. We are reminded later that "though she was not divorced from her legal husband, she agreed to marry" (p. 345). Eleanor McLean also married Parley Pratt without divorcing her first husband. It appears that G. D. Smith hopes to capitalize on ignorance about nineteenth-century laws and practices regarding marriage and divorce. "From the standpoint of the legal historian," wrote one expert who is not a Latter-day Saint, "it is perhaps surprising that anyone prosecuted bigamy at all. Given the confusion over conflicting state laws on marriage, there were many ways to escape notice, if not conviction."  To remarry without a formal divorce was not an unusual thing in antebellum America.
Bigamy or, rather, serial monogamy (without divorce or death) was a common social experience in early America. Much of the time, serial monogamists were poor and transient people, for whom the property rights that came with a recognized marriage would not have been much of a concern, people whose lives only rarely intersected with the law of marriage. 
The legal apparatus for performing divorces was not always readily available
The Saints were often poor and spent most of their time on the frontier, where the legal apparatus of the state was particularly feeble. Women who had joined the church and traveled to Zion without their husbands were particularly likely to be poor, and also unlikely to be worried about property rights. Nor, not incidentally, were their husbands available for a formal divorce.
Does this mean that marriage in America was a free-for-all? Hardly, notes Nancy Cott:
When couples married informally, or reversed the order of divorce and remarriage, they were not simply acting privately, taking the law into their own hands. . . . A couple about to join or leave an intimate relationship looked for communal sanction. The surrounding local community provided the public oversight necessary. Without resort to the state apparatus, local informal policing by the community affirmed that marriage was a well-defined public institution as well as a contract made by consent. Carrying out the standard obligations of the marriage bargain—cohabitation, husband's support, wife's service—seems to have been much more central to the approbation of local communities at this time than how or when the marriage took place, and whether one of the partners had been married elsewhere before. 
It also should be remembered that because Joseph Smith, Brigham Young, and other Latter-day Saint leaders exercised exclusive jurisdiction over celestial or plural marriages, marriages conducted under their supervision had as much (or more) formal oversight as many traditional marriages in America during the first half of the nineteenth century. Critics of the Church often us nothing of this—with the result that some credulous readers might be horrified by the "loose" marriage practices of the Saints.
- "O Casamento Plural e as Famílias Polígamas nos Primórdios de Utah," Tópicos do Evangelho em LDS.org (2013)
- Lynn Hunt, "Against Presentism," Perspectives 40/5 (May 2002); available online at http://www.historians.org/perspectives/issues/2002/0205/ (accessed 2 December 2008).
- Beverly J. Schwartzberg, "Grass Widows, Barbarians, and Bigamists: Fluid Marriage in Late Nineteenth-Century America" (PhD diss., University of California, Santa Barbara, 2001), 51–52.
- Hendrik Harlog, Man & Wife in America: A History (Cambridge, MA: Harvard University Press, 2000), 87.
- Nancy F. Cott, Public Vows: A History of Marriage and the Nation (Cambridge, MA: Harvard University Press, 2000), 37.