Jessica Simpson Vacations in Mexico Without Tony Romo

Tony Romo may have joined Jessica Simpson for pregnant sister Ashlee’s Saturday wedding — but he skipped out on a family vacation with her the next day.

On Sunday, Jessica and her parents Joe and Tina hopped a private jet for some R&R in Cabo San Lucas, Mexico, amidst reports that she and Romo had split.

(Jessica, who toted her dog Daisy on the tarmac, doesn’t seem to have relationship luck in Cabo. After a teary 2007 trip there with John Mayer — who’s currently dating Jennifer Aniston — the pair called it quits.)

On Friday, Usmagazine.com reported that Joe begged Romo to attend Ashlee’s wedding “to support the family.”

That same day, Jessica and Tony were spotted lunching at sushi restaurant Katsuya in L.A. It was the first time they’d been photographed together in three weeks.

So are they really over?

“He’s broken up with her before, but I don’t know if they’ll get back together this time,” a source tells Us.