Jennifer Aniston is reportedly set to walk down the aisle with beau John Mayer, according to a source close to the 39-year-old actress. "She's at an age where she is thinking with her head not just her heart... no way would she still be with anyone if marriage wasn't a real option," a source tells OK! magazine.

Another pal dished that Jen and John's nuptials will not be like the million-dollar affair when she married Brad Pitt. "She doesn't want anything elaborate or showy," the friend told the magazine.

Another source says the two are destined to be together, gushing, "They are just a perfect match." Aniston has been spotted on tour with Mayer, 30.

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