Even the hard-bitten television critics woke up this morning "feeling a little bummed."
"Certain shows you feel more for than others," said the professor of media and popular culture. "And metaphorically, you can be addicted to a special TV show, even if it's not like tobacco or crack or heroin."
Some of the 23 million fans who call themselves "addicts" will experience withdrawal now that the six-season "Lost" has come to a close, but culture critics and psychologists say it is natural to bond with characters who come into the living room every week.
As for "Lost," the interactive plot and cryptic literary references -- characters with names like Hume, Locke and Rousseau, and even a rabbit named Angstrom, a nod to John Updike -- kept viewers involved for six seasons.
A smoke monster, polar bear and even a group of island residents known as the Others provided weekly mysteries for viewers. Even the enigmatic finale Sunday night, which drew 13 million viewers, kept audiences guessing about its meaning.
"The show was huge, and one of the things that made it great was all the possibilities," said Brian Sercus of Wharton, N.J., a confessed addict. "Your imagination always got a workout.
"It's hard to love the ending, just because endings are like that, but by leaving so much unsaid, I think it'll be fun to rewatch the whole series," said the 29-year-old. "Still, there were a lot of beautiful things in the last episode. The series was all about the characters and their relationships, and the finale really paid homage to that fact."
Producers even killed off favorite characters to keep the series fresh, much the same way as HBO's "Sopranos" whittled down the favorites each season, ending in a cliffhanger that fans are still talking about. (Was Tony whacked or did life just go "on and on?")
"We have a tendency to make fun of these people," said Thompson. "There are some who go overboard, but there is nothing wrong and nothing unnatural about feeling a strong connection to these things."
The same could be said of the long-running series "M*A*S*H," which captured the cynicism and antiwar sentiment of the 1970s. The show followed a team of doctors stationed at the 4077th Mobile Army Surgical Hospital during the Korean War.
The series ran from 1972 to 1983, and the finale, "Goodbye, Farewell and Amen," was until the 2010 Super Bowl, the most most-watched television show in U.S. history, with nearly 106 million viewers.
The series "Friends," which wove the relationships of six 20-somethings at a local coffee shop, aired from 1994 to 2004 and drew nearly 53 million viewers to its finale, making it the fourth most-watched series in American history.
Members of Generation X, who are now in their 30s, reacted the same way to the end of "Beverly Hills 90210," the television series about a group of rich students who go to West Beverly Hills High School, which ran from 1990 to 2000.
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"A lot of my students had never remembered a world where there wasn't a '90210,'" said Thompson. "They started watching it young, and it was part of their childhood. Some said they started watching it fairly young and then again while having their first child.
"A show that has been on a long time engenders a strong sense of identity and commitment and can really become an important part of your life. 'Lost' was a major topic of conversation and they did these elaborate analyses on the fan site," Thompson said. "I can understand how some people are feeling a sense of loss at the end."
Not only are the characters gone, but so are the weekly watch parties, discussion groups and even the "Lost" lingo that has infiltrated online dictionaries.
Withdrawal -- or at least a sense of loss -- will accompany the show's demise, though its culture may live on in blogs and social networking sites, according to University of Wisconsin research psychologist Joanne Cantor, who wrote "Conquer Cyberload: Get More Done, Boost Your Creativity and Reduce Stress."
"It's an emotional connection that you have had for a long time," said Cantor. "People talked about feeling bereft at the end of 'M*A*S*H.' Their relationship to television characters has a lot in common with their relations to real people."
Going on websites after the series finale is a lot like going to a funeral and "hooking up with others to keep in touch because of the emotional loss," she said.
Television has much in common with the way people grieve the end of a good book series, such as
"Harry Potter," said Cantor. "We are all reading it at the same time. The characters can be really strong. People want more and they can't get more."
The 1980 PBS episodic drama "The Jewel and the Crown" featured a character "so despicable" that when the actor arrived in the United States, he was derided on the street.
"He had to wear a beard because people would see him and spit in his face," she said. "He was just an actor playing a character."
The bearded man withstanding, "It's a pretty human thing to do, to use entertainment and to have emotions that are real," said Cantor. "It can be rewarding in many ways."
Art, at its best, stirs those emotions and stimulates creativity.
"If we watch shows without these emotional reactions, then we don't get the entertainment value -- and that's the point," said Cantor. "We look forward each week and see these people we admire and have an attachment to"
Psychologists don't worry about the withdrawal unless it's physiological.
Said Cantor, "As long as when they are missing and gone, we aren't so bereft, we can't go to work the next day."