Jordan Strauss / WireImage 1 / 9
Jordan Strauss / WireImage 1 / 9

By Kat Giantis

Earlier this week, Pete Wentz declared, "Life is good," a sunny proclamation that came just days after he was photographed with his arm around wife Ashlee Simpson-Wentz as they shopped in Los Angeles with 2-year-old son Bronx Mowgli.

But on Tuesday, Ashlee, 26, filed for divorce from the Fall Out Boy frontman, 31, after two-plus years of marriage, citing the standard irreconcilable differences, reports TMZ.

"After careful consideration, we have made the difficult decision to file for divorce," they said in a statement (via People). "We remain friends and deeply committed and loving parents to our son, Bronx, whose happiness and well-being remains our number one priority. We ask that everyone honor our privacy as we navigate this next phase of our lives."

Ashlee has reportedly hired legal pit bull Laura Wasser, and she's asking for joint legal custody and primary physical custody of their moniker-challenged son. She's also seeking child and spousal support and wants to drop the "Wentz" from her last name.

According to TMZ, the pair got hitched without a prenuptial agreement, which was an optimistic move considering that Ashlee had big sister Jessica's prenup-free divorce from Nick Lachey as an example.

RELATED: Jessica and fiancé Eric Johnson will definitely have a prenup

So, what went wrong?

"It's really all about Pete's erratic behavior," a source tells TMZ. "She really wanted out."

Adds another insider to Us, "They've been unhappy. They're living two separate lives."

After hooking up in the fall of 2006, Ashlee and Pete tied the knot in May 2008 in a lavish, Alice in Wonderland-themed ceremony at the home of Simpson's parents (Papa Joe performed the nuptials). Bronx arrived six months later.

Just three weeks ago, Ashlee still seemed smitten with Pete, gushingly tweeting to her hubby, "I already miss your handsome face!"

And two days ago, Wentz lovingly complimented Ashlee's mothering skills: "dont forget 2 notice-when i look into the lil dudes eyes & smile, the way he loves. i realize [Ashlee] is a good moma + so much more."

Concludes a source to People, "They're both really sad. It's a sad ending to something that was really promising. They're each trying to figure out what this transition is going to be like."

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