Despite going on a dinner date with Aniston, 41, in New York last year while she filmed her box office dud "The Bounty Hunter," Cooper, 34, downplays their relationship.
"I'm reading about me taking Jennifer Aniston to my Bel Air mansion and having a candlelit dinner, and I was like, 'That's crazy. Never happened,'" he tells the magazine.
Describing Aniston as a pal, he says he even joked to her about various tabloid reports: "Hey, we should hang out — the other dates that we never had went so well."
He clams up when the topic turns to Zellweger, 41, with whom he has been dating since 2009. (The two have gotten so close that she has even met his mother.)
"I just can't," he says when asked about his girlfriend.
He is equally mum about his four-month marriage to actress Jennifer Esposito. "It was an experience," he simply says.
Cooper may get hearts racing this summer with his taut and toned bod in "The A-Team" (out June 11), but he tells Details: "I never lived the life of 'Oh, you're so good-looking.' People thought I was a girl when I was little, because I looked like a girl — maybe because my mother would keep my hair really long in a bowl cut. I was in a coffee shop once and the waitress was like, 'What do you want, Miss?' I was 10 or 11 — the worst age to have that happen. I had a jean jacket on and a Metallica pin. I thought I was really cool."
As for his bulging biceps and concrete pecs in "The A-Team," "I had to literally transform my body," he says.
In addition to cutting out sugar, salt, and flour, he worked out two hours each day with a trainer.
"As the movie progressed, I got in increasingly better shape," he tells Details. "There's this one fight scene with Liam Neeson toward the end, where it's, like, the apex of the work ... I swear to God, it looked like my head was digitally superimposed onto someone else's body. I was like, 'This cannot be me. That's the way I look?' ... 'Cause as a kid I only fantasized about looking that way. Remember Soloflex commercials? That was huge when I was a kid. It was like, 'I wanna be the Soloflex guy. Mom, can we get the Soloflex?'"
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