Of course, Aniston, 39, understands why so many people are intrigued by their romance. There's the age difference – Mayer is eight years younger – and the musician's high-profile past relationships with starlets like Jessica Simpson.
"Did you ever think Claudia Schiffer and David Copperfield made sense?" Aniston says, jokingly comparing her relationship to equally unexpected celebrity couples. "Did Susan Anton and Dudley Moore make sense? Wait! I got more!"
When they met at an Oscar party last February, Aniston says she "barely knew his music." But the two began dating – Aniston flew to England where the rocker was touring – and their relationship developed before the cameras.
Did she know it was going to work out at the time?
"You know, it isn't designed," Aniston says. "Love just shows up and you go, 'Oh, wow, this is going to be a hayride and a half.' "
"I Feel Seriously Protective" of MayerWhen talking about Mayer's famous run-in with reporters outside a gym in Manhattan where he said about their split, "I don't want to waste somebody's time if something's not right," Aniston isn't ruffled.
"He had to put that out there that he broke up with me," she says, about Mayer's comments. "And especially because it's me. It's not just some girl he’s dating. I get it. We're human. But I feel seriously protective of him and us."
Adds Aniston: "It's funny when you hit a place in a relationship and you both realize [that] we maybe need to do something else, but you still really, really love each other. It's painful. There was no malicious intent. I deeply, deeply care about him; we talk, we adore one another. And that's where it is.”
On Her Relationship with Brad PittEqually candid about her ex-husband, Brad Pitt, Aniston says she has spoken to him since their divorce, and calls their split "amicable."
"The marriage didn't work out," she tells the magazine. "Pretty soon after we separated, we got on the phone and we had a long, long conversation with each other and said a lot of things, and ever since we've been unbelievably warm and respectful of each other."
(Aniston also shares some thoughts about Pitt's partner, Angelina Jolie, with the magazine.)
Aniston, who says she's been "unbelievably lucky in love," is also practical about the subject. "Whoever said everything has to be forever," she says. "That's setting your hopes too high. It's too much pressure. And I think if you put that pressure on yourself … that's unattainable."
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See Jen & John's sizzling vacation!
2005: Revisit what Jen said about Brad after their split