"They are so comfortable and at ease with each other," a mutual pal says of the duo. Photo by: Jean Baptiste Lacroix / WireImage
Drew's Bliss| Drew Barrymore Cover, Drew Barrymore, Justin Long
Her new relationship bliss caps off what has been a transformative year for Barrymore. When the CoverGirl spokesmodel wasn't setting off flashbulbs on the red carpet, she was behind the camera filming her passion project – a documentary on school feeding programs in Africa for the WFP. Along with her usual running ritual on the treadmill, Barrymore became a devout follower of the ballet-influenced Bar Method workout that helped her shed almost 15 lbs. to play socialite "Little Edie" Beale in the upcoming HBO film Grey Gardens (a former vegetarian, Barrymore relies on a regime of veggies and protein but occasionally indulges in her favorite – macaroni and cheese). But the biggest change occurred last January, when her relationship of more than four years with the Strokes' drummer Fabrizio Moretti ended. Back on the market, the famed free spirit hit the singles scene, hooking up with director Spike Jonze and Zach Braff before getting serious with Long. "At some point you decide who you want to be and the person you want to become, and you grow up and you make different choices in life," Barrymore told Winfrey, adding "[Justin and I] are very, very fortunate."

So much so that the former wild child and the Vassar-educated actor best known for his commercials for Apple computers have already had serious talks about their future. "They have talked about having kids, growing old, retiring," says the couple's friend. "Drew loves everything about him, and Justin really admires her. They're both in this for the long run." A tell-tale sign of their commitment? The actor took Barrymore to Fairfield, Conn., to celebrate Thanksgiving with his tight-knit family. When the actress joined Long, his younger brother, fellow actor Christian, 26, and some friends at a local bar, "Drew was laughing and seemed like she was part of the gang," says a witness. And when the couple hit Florida, they spent quality time with another important woman in his life: his grandmother. The trio went out to dinner at an Italian bistro in Palm Beach, where Long picked up the tab. "It was a family outing," says a source.

While she's passed muster with his relatives, Long has seamlessly blended into Barrymore's clique. "All our friends get along great, which is awesome because we travel together in packs," Barrymore said on Oprah. The actress brought her beau to the December wedding of Jimmy Fallon and her close friend and business partner Nancy Juvonen. Long then joined Barrymore and her buddies, including Cameron Diaz, for a Bahamas getaway. They also party together back home in L.A., where Barrymore celebrated her 33rd birthday at the Soho House outpost in West Hollywood on Feb. 21 with Long and a passel of pals. "Justin was by her side the entire night," says an observer. "They were dancing like crazy. She could not have looked happier."

That is, until four days later, when the pair escaped to a remote resort in Tulum, Mexico, where they transformed a thatched roof villa into a romantic retreat. By day "they spent time sitting on the beach just talking for hours," says a fellow guest. At sunset, "they held hands as they walked along the water and seemed at ease. They were both in great moods, obviously having a good time. They seemed in love." And, a friend says of Barrymore, it shows. "She's looking better than ever, which means she's happy – he's good for her." By

Michelle Tan. Reported by Jennifer Garcia, Maureen Harrington and Mary Margaret in Los Angeles, Steve Helling and Linda Marx in Miami and Charlotte Triggs and K.C. Baker in New York City
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