
Now that his marriage to
Ashlee Simpson is officially over ...
Pete Wentz hit the town with his NEW model girlfriend
Meagan Camper in L.A. last night.
While his marriage lasted 3 and a half years, Pete and Meagan have been dating for just about three months.

They said it wouldn't last ... and they were right -- because
Pete Wentz and
Ashlee Simpson are officially divorced ... after a judge signed off on the split.
According to court docs filed in L.A. County Superior Court and obtained by TMZ ... the marriage was formally terminated on November 22 ... after a 3-and-a-half year run.
As for the couple's kid --
Bronx Mowgli -- it's unclear how the couple settled their custody disagreement ... because the details of the divorce settlement are being kept under wraps. TMZ previously reported, Pete wanted joint custody of their son ... but Ashlee had checked the box to get primary physical custody.
The former couple also worked out a secret deal regarding the division of their multi-million dollar empire.
As we previously reported, Wentz chalked up the split to the couple simply growing apart.
It appears
Ashlee Simpson can use her mouth for more than just not singing live
, as she was spotted making out with her new man -- actor
Vincent Piazza -- in NYC on Monday.

In February, Ashlee & her husband
Pete Wentz filed for divorce after nearly three years of marriage.
While the former couple were seen
out and about with their son Bronx, it appears any hope of a reconciliation are off.
Ashlee Simpson and
Pete Wentz are finally coming to grips with their divorce ... by holding hands during a coffee run today in L.A. with their son
Bronx.

Ashlee and Pete have been spotted out together numerous times since she filed for divorce last month ... but this is the first time we've seen them getting physical.
How touching.
Ashlee Simpson feels badly that
Petz Wentz is hurting over their impending divorce, and that's why she spent time with Pete over the weekend -- she is NOT getting back together with him.

Ashlee and Pete
hit up In-N-Out and Taco Bell, but there is no reconciliation. Pete is leaving town today for a month-long series of concerts, and she wanted to boost his spirits before he left.
Our sources say Pete never wanted the divorce and would get back with Ashlee in a second, but she definitely wants out of the marriage.
They're both trying to stay on good terms for the sake of their son, Bronx.
Divorcing couple
Pete Wentz and
Ashlee Simpson put their child custody battle on hold this weekend ... to enjoy a little drive-thru action together at
In-N-Out Burger in Hollywood.

Never underestimate the reuniting power of a Double-Double.
Pete Wentz does NOT want his soon-to-be-ex wife
Ashlee Simpson to get primary physical custody of their 2-year-old son
Bronx -- as she's requested -- and now he's taking her on in court ... TMZ has learned.

Wentz just filed legal papers in response to Ashlee's divorce petition ... asking the judge for JOINT physical and legal custody of their son. In her divorce petition, Ashlee checked the box that indicated she wanted primary physical custody.
According to the docs, filed in L.A. County Superior Court and obtained by TMZ, Wentz also wants each party to pay their own legal fees ... even though Ashlee asked the court to make Pete foot the bill for both sides.
And while Ashlee didn't specify the official break-up date in her papers -- Pete says the two called it quits on Feb. 9 ... just days after Pete came home from a wife-less trip to Dallas for the Super Bowl.
Pete Wentz flew to Japan for some event on Friday ... but left his wedding ring at home.

Earlier this week, the 31-year-old
reunited with his estranged wife Ashlee Simpson for a little Valentine's Day lunch.
But Friday, Pete didn't put a ring on it, so it looks like he's single, ladies.
Divorcing couple
Pete Wentz and
Ashlee Simpson enjoyed an amicable
Valentine's Day lunch with their son
Bronx at the Beverly Hills Hotel today.

Sometimes irreconcilable differences can bring people together.
It's as if
Ashlee Simpson and
Pete Wentz were in two different marriages ... sources connected with the couple tell TMZ.

TMZ broke the story ... Ashlee filed for divorce Wednesday. Turns out she's been "extremely unhappy for a long time," so says one source familiar with the situation. Ashlee has wanted out of the marriage for a while.
Meanwhile, Pete was happy with the marriage and had no idea Ashlee had reservations about the union.
When Ashlee told Pete she wanted out, he begged her to change her mind, our sources say. As recently as yesterday, Pete has been crying, asking Ashlee to give the marriage another try.
We're told Ashlee isn't budging. As we already reported, she feels Pete's "erratic behavior" has made the marriage impossible.
Pete Wentz is getting divorced against his will -- so say sources close to the rocker ... he absolutely did not want to end his marriage to
Ashlee Simpson.

We're told Wentz tried talking Ashlee out of filing divorce papers, to no avail. She wanted out of the marriage ... sources tell us.
In fact, Wentz was flashing his wedding ring and a HUGE smile all over Dallas this past weekend -- while his wife was back home in L.A. with their son
Bronx.
We're told Pete was partying like he didn't have a care in the world Saturday night at the
Mercedes-Benz Tweet Race -- even posing for a pic on a massive live bull -- but not once did he mention anything about a possible divorce.

As TMZ first reported, Simpson filed divorce papers Wednesday morning -- and we're told the issue for her was Pete's "erratic" behavior.