Mistry alleges that the visa process was started well before the marriage, suggesting that the Udwadias intended to find free household help, rather than a wife for their son.
But the Udwadias claim that the visa application began after the wedding, and that Mistry's father had even engaged an agent to help push it through.
In 2006, when Himansu Udwadia could not find a potential bride through online dating sites, he turned to his parents for help, according to the defense.
The Udwadias and their two sons traveled to Navsari, India, and allege that "word spread quickly" that a Canadian citizen working in the U.S. wanted a bride.
Potential fathers of the bride submitted biographical data to the family, and if Himansu Udwadia was interested, he arranged a meeting, they said.
He met 15 to 20 women over a two-week period, according to court documents. One of them was Mistry, whose details, they allege, had been supplied by her father.
The two met briefly to see if they were compatible and after a second longer date, agreed to marry.
"The wedding was a grand and expensive celebration," according to defense lawyers. They also claim that Mistry was given five wedding dresses from the Udwadias, costing about $2,000, as well as gold jewelry valued at about $4,000.
Although Mistry alleges that the Udwadias dashed her plans to finish college, they counter that she had failed her second year of school and had no tests to take. They also allege that there was never an agreement between the couple that she should finish her education.
They allege in court documents that at the time, Mistry "could not be more excited" about moving to the U.S.
Both parties agree that soon after the marriage took place, Himansu Udwadia left the family's Oklahoma home and moved to Georgia to work as an accountant, leaving his wife alone with her in-laws.
But the Udwadias allege that the newlyweds had discussed the job opportunity, and "it was agreed it was the right move for them to make, even though they would live apart for a period of time."
Once he was "financially on his feet," Himansu Udwadia moved into an apartment, and Mistry joined him, say the Udwadias.
The lawsuit alleges that during that time apart, the Udwadias were able to control Mistry by threatening her with divorce, which she says in her culture would carry "deep shame" and rejection.
The family also forbade all unmonitored communication with Mistry's parents, Mistry alleges in the lawsuit.
"They also took all of my personal belongings once we got to the U.S., and kept them from me," Mistry wrote. "But for a long time, I told myself that I had to accept the harsh treatment because I was scared. ..."
According to the lawsuit, Mistry was forced to rise at 5 a.m. to prepare tea and breakfast for her in-laws, then spent the day cleaning the pictures of the Hindi gods, picking flowers for prayer, doing laundry and feeding the dog, working until 11 p.m. every day, even when she was sick.
The Udwadias say in court documents that Mistry "helped around the house" and also took care of the family dog, but "no one forced her to do so."
They claim Chandrakant Udwadia was "particular" about his tea and made his own in the morning.
In November 2007, Mistry went to Georgia to join her husband, but the control continued, according to the lawsuit.
Mistry alleges she continued to be monitored at a distance by webcam, and that her husband reported back to his parents. She also alleged she was forced to work at Dairy Queen and had to turn over all her wages to the Udwadias.
But the defense claims that the couple "did not get along" and Humansu Udwadia often slept on the couch. By March 2008, he asked for a divorce, which was finalized in October of that year, the defense maintains.
Mistry said she was sent back to India under the false pretense that she could return to school, according to the lawsuit. She alleges her father-in-law initiated the divorce.
Mistry's parents were "supportive" of their daughter when they learned the truth, according to her lawyers, but she decided to return to the U.S. to confront her husband when he did not return her calls.
She had an uncle living in Clearwater, Fla., and there, Mistry sought help with her visa from Catholic Charities, where social workers encouraged her to contact human trafficking advocates.
According to Giselle Rodriguez of the Florida Coalition on Human Trafficking, the FBI attempted to file criminal charges, but the U.S. and state attorneys "passed up on the case" because "they didn't know if it would stand in court because of the Hindi customs [in marriage]."
The FBI granted Mistry a "continued presence" as a refugee in the U.S., she said.
"It was really difficult for her," said Rodriguez, the caseworker who helped Mistry find shelter, food and clothing. "When I first met her, she was very lost. They had made her cut her hair off, and she was down to 90 pounds and looked extremely sad."
The Udwadias deny those claims and say Mistry was "healthy, as is obvious" in photos taken up until January 2008.
Her lawyers have told ABCNews.com that the lawsuit meets many of the legal criteria of human trafficking: involuntary servitude, misleading statements to induce a victim to enter a situation, threats of deportation, long work hours and restricted access to food and medical care.
Mistry would not explain to ABCNews.com why she had not named her husband, Himansu Udwadia, in the lawsuit.
Today Mistry resides in another part of the United States and said she still struggles with depression and anxiety, and at times feels suicidal.
The Justice Department says that there are currently 2,525 cases of human trafficking under investigation.