12 Secrets About Jennifer Garner & Ben Affleck's Split—Photos!

As their 10-year wedding anniversary, on June 29, draws closer, insiders say that Ben Affleck and Jennifer Garner are preparing to tell the world they're separating. The sad announcement has been a long time coming.

Now, as Ben searches for a bachelor pad, insiders say Jen is working out how to get the best possible settlement from him, should their separation result in divorce. Star has the inside scoop on the heartbreaking demise of their marriage—and how they'll split their $150 million fortune.

Friends of the couple say that Ben, 42, has been planning his exit for a year. "He was considering moving out in 2014 and even went apartment hunting in New York City," the insider says.

But when Jennifer, 43, found out her husband had been searching for a bachelor pad, she insisted they make a last-ditch attempt to save their marriage by going to therapy together.

That's when he started spending most nights away from home—as Star reported, he's been staying at hotels and at longtime pal Matt Damon's house—and she began picking up his things. "Jen is getting ready to move on, and so is he," the insider says. "He can't wait to go back to being the man he was before they met."

"They've been living separate lives for so long, because of their careers, that Ben is moving out won't be a huge adjustment for her," says a friend. "But she's still heartbroken. This is extremely hard for her."

"It's no surprise that Ben enjoys gambling his nights away—and nothing good comes from being up all night drinking and gambling, especially in a place like Las Vegas, where call girls are everywhere," the insider notes. "Jen is terrified that cocktail waitresses, hookers, and party girls could come out of the woodwork and claim to have hooked up with Ben. She's never busted him cheating, but she's no fool. There's been buzz about it for years, and she has no idea what he's up to much of the time."

If divorce is in the cards for the couple, Ben stands to lose a lot. Jennifer has been controlling their finances for years, and insiders say she'll fight tooth and nail for as much of their amassed $150 million fortune as she can. "They didn't sign a prenup, and she's very savvy when it comes to their assets," the spy reports. "She knows exactly what they have and where it's invested."

On top of that, Jen has made serious sacrifices in her own career to support Ben and to care for their children. "That's the reason she's not worth as much as him: because she's put her family first. She thinks she should be rewarded for that," the insider adds.

"She'll do anything for those kids, even if it means fighting mercilessly for Ben's money and their family's house," dishes the insider.

One thing she probably won't have to fight for is custody. While Ben adores his children, insiders say he's not sure he's capable of parenting them full-time. "He loves his bachelor life too much, and the past few months have opened his eyes to that more than ever," the friend says.

"Everyone says Jen made him a better person, but he's tired of being tamed. At this point, it seems like divorce is imminent," adds the insider.