After years of speculation and on-again, off-again rumors, it looks as though Jennifer Aniston is finally going to walk down the aisle again. According to a source close to the actress, she and her fiancé Justin Theroux have finally set their wedding date.

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According to OK Magazine on Thursday, the couple will be tying the knot by the end of this year.

An insider tells the magazine, "It's really happening! Jen is excited beyond belief. She says it will be the best day of her life."

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What's more, Aniston is supposedly trying to keep the day a "big secret" from her family and friends, too.

The source added, "If you try asking, she'll change the subject to keep everyone guessing. Neither of them wants a huge, glitzy wedding."

Meanwhile, there were rumors earlier this week that suggested that Theroux might be getting "cold feet."

According to Cover Media on Monday, Aniston's friends are concerned that the actress is wasting her time with Theroux, as he isn't showing any signs that he is interested in tying the knot with the 45-year-old actress.

A source told Grazia Magazine's print edition, "Several of Jen's friends, including Chelsea Handler and Demi Moore, are thought to have urged caution over Justin's reluctance to carry out the wedding, pointing out his reputation as a huge commitment-phobe. Even Justin's own friends have joked that his like 'we're not on anyone else's time frame' should be 'we're not on any time frame.'"

What's more, Theroux is supposedly mimicking the same behavior he did when he was in a 14-year relationship with his ex-girlfriend, Heidi Bivens, who he refused to marry as well.

The insider added, "One moment Justin would be dropping hints to Heidi about 'when we're married,' before getting really vague and ultimately dismissing it as just a piece of paper. Justin seems hesitant to even discuss the kind of ceremony he'd like [with Jen]. Their recent trip to Bora Bora was a typical example - it seems Jen wanted the beautiful setting to inspire them to talk about romantic wedding locations, but it seems Justin has become a pro at deflecting her hints."

Aniston and Theroux have been engaged since August 2012.

Tags: Jennifer Aniston Justin Theroux