When Hollywood A-listers Brad Pitt and Jennifer Aniston were photographed having a sweet reunion at the 26th Screen Actors Guild Awards last month, left and right rumors about the ex-lovers getting back together immediately sparked. 

While the ex-husband and wife are now both single and there is nothing wrong if they get back in each other's arms, it looks like third parties (particularly their exes) would not let them live happily ever after.

It is after Jennifer's second ex-husband, Justin Theroux, is said to be releasing a tell-all revelation about his life -- including the episodes where the "Friends" alum is on it. 

As the anniversary of Justin and Jennifer's separation is nearing, he is once again alleged to drop a bombshell against his ex-wife of two years.

Rumor has it that the 48-year-old actor has been getting offers to write a book right after he and Jenn split up in February 2018. However, Justin has been holding his guard, not until now. 

Justin's Ego 

According to a source, now that Jennifer has reportedly rekindled her romance with the "Once Upon A Time In Hollywood" actor, it feels like Justin's wound from the failed marriage resurfaced.

"He's not a bitter guy by nature, but the fact she's back with Brad has cut him pretty deep and really bruised his ego," a source told New Idea

"Justin spent much of their marriage feeling like he was this substitute version of her ex, but she'd assure him time and time again that wasn't the case."

It turns out the actor/director has been using writing as a way of healing since the breakup with Jen. It was not his intention to spill the rotten beans from his marriage with "The Morning Show" star, it was just his way of noting down the ups and downs of his life. 

The juiciest part of Justin's tell-all could be revealing how it was like being married to someone who is still head over heels with their ex. 

Brad and Jen Under Justin's Mercy

The source also revealed that the 56-year-old Brad and 51-year-old Jen has been freaking out upon learning about Justin's plan. 

The insider added that Brad reached out to Justin, pleading him not to include passages about him and Jenn on his writings. 

"They've had a few chats over the phone, and Brad has made the point that this was hurtful and wholly unnecessary, to go so low and dish out secrets he and Jen don't want (to be) told," the source claimed. 

But it looks like Justin is eager to make this "no-holds-barred" book to happen and explained to Brad that he is entitled to write the book in whatever ways he wants. 

The source added that Justin did not sign a non-disclosure agreement upon divorce with Jen, so there is no stopping him from exposing the real deal. 

"There's nothing she or Brad can do to change his mind - and he's not going to hold back," the source said.

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