It was a Halloween they won’t ever forget. At her historic $25 million Beverly Hills mansion on Oct. 31, Angelina Jolie let her six children “throw a huge party,” a source tells In Touch exclusively. “The house was done up like the ultimate fright fest.” They dyed the pool water red to make it look like blood, hauled in a fog machine to up the spook factor and decked the 11,000-square-foot house with hand-selected decorations. (Angelina was spotted dropping $1,000 on costumes and decor, including a fake dead bird in a cage, at the Glendale, CA, store Glendale Halloween in early October.) “It was special,” continues the source. “All of Angie’s and the kids’ friends attended.” On the guest list: Japanese rocker-actor Miyavi, who starred in Angelina’s Unbroken, and Loung Ung, the author whose life story Angie told in First They Killed My Father. “Everyone the kids hold near and dear was there.”

Except their dad, Brad Pitt. “He was deeply hurt he couldn’t be a part of it,” says the source. In the 14 months since Angelina, 42, blindsided him and filed for divorce, “Brad realizes how much he’s been cut out of the kids’ lives.” But he’s not giving up and is determined to keep his bond strong with Maddox, 16, Pax, 13, Zahara, 12, Shiloh, 11, and nine-year-old twins Knox and Vivienne. While being a dad comes first in his life, he’s also reestablished a very special relationship — his connection to Jennifer Aniston, the woman he left for Angelina in 2005. And after months of talks and texts, they’ve grown closer than ever. “Brad’s conversations with Jen have helped him negotiate his new life as he’s getting divorced,” says the source. “He feels a deep connection with her.” And while the source insists that Brad, 53, “would never dream of” coming between Jen, 48, and her husband of two years, Justin Theroux, 46, if they were to break up, “Brad would take a second chance at love with Jen in a heartbeat.”

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A Jen and Justin breakup is not out of the realm of possibility. The couple, who first became involved after they worked together on the 2012 movie Wanderlust, “have had their fair share of marital problems,” says the source. For starters, “they spend more time apart than together, with him preferring NYC and her LA,” continues the source. Jen and Justin were photographed together on Oct. 1 in NYC and then weren’t pictured together again for the rest of the month, and then some. And since Sept. 1, he’s hit the red carpet for his new movie The LEGO Ninjago Movie solo, attended an event at Legoland in Carlsbad, CA, alone and has been spotted in NYC without Jen nine times.

Filming for his HBO drama, The Leftovers, also took him to Australia for an extended period of time recently. “He revels in far-flung locations,” says the source. “And she’s a California homebody.” It’s just one of their many differences. Jen, the bubbly girl-next-door type, and Justin, a brooding, tattooed motorcycle aficionado, “basically have little in common,” says the source. She and Brad, however, still have an intense bond. And it’s something the exes, who were first set up on a date by their publicists back in 1998, are realizing as they have reconnected as friends. As In Touch previously reported, over the summer, Brad reached out to Jen to apologize for the way he treated her in their marriage. “He came off as genuinely sorry, and Jen was deeply touched,” an insider said at the time. “She was completely won over.” She was so charmed, in fact, that they have continued to talk. One of their frequent topics of conversation: Brad’s painful split from Angelina, their custody battle and how she tried to painted him as a villain after an incident involving Brad and their sons aboard a private jet in September 2016. “Jen’s completely on Brad’s side when it comes to getting joint custody of the kids,” says the source.

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“Jen has a way of calming and encouraging Brad.” Following his split from Angelina, Brad got sober and entered therapy, “and he’s in touch with emotions and his true self like never before,” adds the source. “He’s come to realize that leaving Jen for Angelina was one of the biggest mistakes of his life. And while he’s not in love with Jen, he realizes how much he does love her. Brad keeps telling friends that he’s seeing everything more clearly.”

One thing he envisions: much more of Jen in his life. Even if they can’t be together romantically, he wants to work with his ex. When they were married and formed the production company Plan B in 2001, “they really worked well together as partners,” says an insider close to Brad. “He wants Jen involved again as he produces and develops more and more high-quality film and cable TV products.” Well aware that Brad won best picture Oscars for producing 12 Years a Slave and Moon- light, “Jennifer wants in on such prestige projects,” adds the insider. “She’d be beyond thrilled to win an Academy Award for best actress — something that’s evaded both her and Angelina — under Brad’s production banner.”

The friends also want to partner on non showbiz projects. Both of them are into renovations and “they were always working on ideas for homes together when they were married, and they’ve already been talking about ideas for future house and building projects,” says the insider. “It’s something he’s always shared with Jen, as opposed to Angelina, who couldn’t care less about interior design or home renovation.” Indeed, she told Vanity Fair recently that design “was always Brad’s thing…I didn’t even know I needed throw pillows.”

It took a painful divorce — and 12 years apart — for Brad and Jen to realize how in sync they are. “They have reached a level of closeness and understanding that they never had when they were married,” says the source. What that means for them in the future is very much up in the air. But one thing is certain as far as Brad is concerned, says the source: “He still considers Jen the love of his life.”