HOLLYWOOD - At 46, Nia Vardalos is enjoying the best role of her life - mother.

The star and writer of the comedy hit "My Big Fat Greek Wedding" adopted a little girl about a year ago and she couldn't be happier.

"It's the best thing that ever happened to me," the actress said. "My daughter makes me laugh every day."

After about a decade of fertility treatments, Vardalos and her husband, actor Ian Gomez, opened up to the possibility of adoption. (She declines to give her daughter's name in order to protect her privacy.)

While some celebrities aren't as forthcoming about their personal trials, Vardalos feels a need to get the word out about adoption because she feels passionately about it. "It's not for everyone, I understand," she said. "But I feel the choice was made for me. Cosmically, I was supposed to be this little girl's mother."

Vardalos reveals that while she was enjoying the phenomenal success of "My Big Fat Greek Wedding," she was at a low point emotionally over her inability to conceive - even enduring years of painful medical treatments.

"I just withdrew," she recalled. "I didn't want to be on camera. I grieved so hard because I was raised with the philosophy that if you work hard, you could achieve anything. But you can't fight Mother Nature."

After "Greek Wedding" and the box office miss "Connie and Carla," Vardalos focused on her writing, completing six screenplays and doing some side work for her pals Tom Hanks and director Jonathan Demme. "I poured myself onto my computer keyboard," she recalled.

With her family now complete, Vardalos is ready to make audiences laugh and smile again. She stars in the comedy "My Life in Ruins," playing a Greek-American tour guide bored with her job of entertaining tourists. Through a series of comical incidents, she rediscovers her mojo.

Mike Reiss, a writer for "The Simpsons," penned the script with her in mind. Vardalos wasn't sure she wanted to star in the comedy when she read it, but she knew she wanted to see it made and brought it to Hanks and his co-producers. She rewrote the script, adding some comedy bits and fleshing out the main character.

"Mike made the cake; I simply added the icing," she said.

Vardalos, who has visited her parents' native land many times, has actually overheard tourists at the ancient temple atop the Acropolis in Athens comment, "That looks just like our IHOP in Washington." That, of course, was fodder for the script.

"Of course, I hear myself saying Americanisms all the time," she confessed.

Thanks to her success with "My Big Fat Greek Wedding," she has become a favorite daughter in Greece. She was able to open doors for director Donald Petrie ("Miss Congeniality") and his crew. The Greek cultural ministry, which usually prohibits film shoots at the country's historic sites, made an exception for Vardalos and "My Life in Ruins." They were allowed to shoot at the Parthenon as well as at the ancient historic sites of Delphi and Olympia, with some restrictions.

"The restrictions were really obvious things like, you can't close the ruins off to tourists while you're shooting and don't show the characters drinking beer at Olympia," she recalled. "I was worried it was going to be something like, you have to put my 'thea' [aunt] in the movie."

Vardalos enjoyed working with co-stars Rachel Dratch, Rita Wilson and Richard Dreyfuss. Because much of the action takes place on a tour bus, the actors were together for most of the shoot and became friends.

"It was like camp; we all stayed at the same hotel," she recalled. "You saw them at breakfast, you saw them in the makeup trailer and, of course, you saw them on set. If you wanted personal space, then you had to hide behind a tree."

Vardalos didn't mind the crowd. The adoption was in the works and she was starting to get her own mojo back, just as her character does. (Her husband has a cameo as a sleazy hotel clerk.) "It was a great time of healing for me," she said of filming in Greece. "I felt a sense of calm and peace while I was shooting this movie."

She also dropped about 40 pounds, thanks to dieting and exercise. "I call it the eat less and move around more diet," she deadpanned.

Vardalos fans will be getting a twofer this summer. She reunites with her "My Big Fat Greek Wedding" co-star John Corbett in "I Hate Valentine's Day," a romantic comedy she wrote and directed. The reunion, she said, is a coincidence.

"I wrote it with another actor in mind," she revealed. "But by the third or fourth draft, he couldn't do it. Our director couldn't do it either, for financial reasons, so the producer said to me, 'Why don't you direct it too?' I said, 'What? I'm a new mom. Are you kidding me?' "

Nevertheless, Vardalos stepped behind the camera and had a ball. "It was like jumping into an orgy while still shaving your legs," she said in her colorful way.

She and Corbett play veterans of dating disasters who have different approaches to dealing with the art of romance. She avoids long-term relationships by restricting her outings to five dates. He plays a guy who's fast and loose in his dating habits.

The actress said it was fun reuniting with Corbett. "It was like old times," she said, smiling.

The Winnipeg native hasn't firmed up her next project but she's buoyed by the newfound happiness in her personal life.

"I've realized I'm an optimistic person," she said. "I highly recommend losing your mojo because you come out of it quite refreshed and with a new perspective." *