The truth is out there. So is the end. "I think on the whole I'm in denial," "X-Files" star Gillian Anderson told the Associated Press about the end of her show after a nine-year run. "There was a point last week when I was driving home from work at about 1 o'clock in the morning, and I tried to imagine myself making that trip, imagine it was the last night. Anytime I got even close to a hint of emotion around it I had to push it away," she said. "It's so huge. It's such an extraordinary transition to have to weather, I'm trying to push it off for as long as I possibly can." The two-hour final episode of the Fox alien-hunting series, in which Anderson, 33, will be re-teamed with her former costar, David Duchovny, 41 (their characters are named Dana Scully and Fox Mulder, respectively), will air on Sunday, May 19. "I started out as a kid. I started out as a 24-year-old, pretending I was 29, and then becoming 29, getting into my 30s and having to grow up myself," she told the news service. "And the character shifted gradually over time alongside my own maturing process." Along the way, Anderson married production designer Clyde Klotz (in 1994, and the union lasted five years) and had a daughter, Piper, now 7. Next up for the actress and onetime Queen of the Net (early in the series' run she was PEOPLE.com's most downloaded celebrity): This fall she'll appear on stage in London's West End in the new Michael Weller play, "What the Night is For." But, for now, says AP, she plans to relax and travel.