Another Man Tore Ashlee and Pete Apart

Ashlee Simpson and Pete Wentz had lunch together with son Bronx in Beverly Hills this week, giving some hope to shell-shocked friends that they might reconsider their divorce. Insiders tell me, however, that's not

going to happen if Ashlee's dad, Joe Simpson, has his way.

"Just like when Jessica split from Nick, Joe is doing nothing to encourage Ashlee to give the marriage another try, if only for the sake of her son," an insider tells me. "Joe likes being the only man in his daughters' lives and is happy that Ashlee has moved back into his home [in Encino, Calif.], just like Jessica did after she announced she was leaving Nick."

Ashlee and Pete married in May 2008, when Ashlee was 23 and Pete was 28. Their son Bronx Mowgli Wentz was born later that year. A source told PEOPLE that the real reason for the split was that they married too young. (Twenty eight is young?)

In their only statement on the split, the pair claimed they "remain friends and deeply committed and loving parents to our son Bronx, whose happiness and well-being remains our No.1 priority."

Pete, who is said to be devastated by the news, has been begging Ashlee to reconsider and has even reached out to her parents in a last-ditch effort to get her back.

"Joe got rid of Nick, and now he is saying goodbye to Pete," a friend of Pete's tells me. "Let's hope Ashlee finds more happiness than Jessica did when she finds herself officially single again.