Kenlie Tiggeman, Southwest's 'Too Fat To Fly' Passenger, Sues Airline (VIDEO)

The story of Kenlie Tiggeman, a New Orleans woman who has lost over 120 pounds in the past two years, made waves last summer, when she went to board a Southwest flight on Easter Sunday in Dallas with her mother.

Tiggeman claims that a Southwest employee quizzed her about her weight and told her she was "too fat to fly" on the airline after Tiggeman asked what the weight restrictions were on the flight.

Tiggeman told MSNBC at the time, "It doesn't matter how far I have come. I have a long way to go, but no one sees that. All they see is my exterior -- someone who is fat."

Southwest's "Customer of Size" policy states that passengers who cannot fit between the 17-inch armrests must purchase a second seat.

Now Tiggeman is taking legal action against the airline. She filed an injunction pro se (without representation) against Southwest on April 20, Nightline reports, alleging that agents "did not follow their company policy and chose to discriminate, humiliate and embarrass" her and that the airline uses "discriminatory actions ... toward obese customers."

Tiggeman is fighting for an industry standards. "If you're telling me I have to buy two seats, you should tell me at the point of purchase, not the day I'm flying when I check in at the terminal," she said.

She added to New Orleans' WDSU, "I understand Southwest wants everyone to be a certain size, but no one knows, including Southwest, no one knows what that size is."

In a statement to Nightline, Southwest spokeswoman Brandy King said she was aware of the suit, but had yet to confirm it with the airline's legal department, adding: "We realize that it's a sensitive conversation and we train our Employees to approach the situation as discreetly as possible. The ... best case scenario is for the Customer to notify us of any special needs ahead of time. If providing the additional seat does not result in our having to deny another Customer boarding, we will refund the ticket to the Customer at no charge, which happens more than 90 percent of the time."

U.S. airlines have had a long history of struggling to deal with customers of size. In February 2010, director Kevin Smith was famously booted from a Southwest flight after being told he was also "too fat to fly." In July 2010, the airline reportedly booted a thin passenger on a flight from Las Vegas to Sacramento to make room for an overweight passenger.

In October 2011, AirTran adopted parent company Southwest's "Customer of Size" policy amid something of an uproar. In February of this year, it was announced that the U.K. was debating a so-called "fat tax" for overweight passengers.