Tori Spelling Is Ready to 'Move on' from Ex Dean McDermott as She Celebrates Her 51st Birthday: Source

Tori Spelling is ready to start a new chapter as she celebrates her 51st birthday.

More than six weeks after she filed for divorce from her husband of 18 years Dean McDermott, a source tells PEOPLE that the Beverly Hills, 90210 alum “is sad but relieved her split is formally moving forward.”

“She knows the whole process was long overdue but it's never pleasant to deal with the details of an unhappy relationship that went on so long,” the insider explains. “She is OK and busy, so she will just have to endure this and fight for the children and however the money sharing goes down.”

The source notes that Spelling is prepared for a potential court battle over both financial and custody issues in their divorce. "She will be much better when she can totally move on with her life," says the insider.

The source claims that Spelling stayed with McDermott for nearly two decades for the sake of their five kids — Liam Aaron McDermott, 17, Stella Doreen, 15, Hattie Margaret, 12, Finn Davey, 11 and Beau Dean, 7. McDermott previously admitted that he “inflicted a lot of pain” on his estranged wife in a November 2023 interview with the Daily Mail.

“They have always cared for each other but problems in the marriage caused Tori to feel insecure and that created marital problems on its own. It has been a vicious circle of misery for both of them,” the source says, noting that the pair will continue to remain "civil" for their kids.

For Spelling, that has included embracing McDermott's girlfriend, Lily Calo, a senior account executive at health brand Conscious Community Global. McDermott and Calo took their relationship to the next level on May 15 by posting photos together on Instagram.

“Love you both ❤️🙌,” Spelling commented on Calo's post. She also liked McDermott's.

A second entertainment source agrees that the divorce has been hard for Spelling, but says she's looking forward to moving on. In the meantime, the source says Spelling has been staying "busy" with her family and "work projects."

“She will do what is necessary and best for the kids," the second source says of the ongoing divorce. "This is not a new thing in her life. She is doing alright and will be happy when things are settled."

A rep for Spelling declined to comment when reached by PEOPLE. A rep for McDermott did not return PEOPLE’s request for comment.

The update on Spelling comes as she celebrates her 51st birthday on Thursday, May 16, and nearly two months after she filed for divorce from McDermott on March 29.

In court documents obtained by PEOPLE, she cited irreconcilable differences as the reason for their split. Their official date of separation was listed as June 17, 2023, the same day that McDermott posted a since-deleted announcement on Instagram that the couple had decided to go their “separate ways” and “start a new journey” apart. 

In a filing of his own on May 13, McDermott disputed part of Spelling's petition, citing July 7, 2023 as their date of separation. He also pushed back against Spelling's request for sole physical custody of their five kids and requested joint physical and legal custody instead.

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Since filing for divorce, both Spelling and McDermott have spoken out about the demise of their relationship and the reasons behind their divorce.

In November 2023, McDermott told the Daily Mail that the couple "had been having problems" for a while but "it just got worse because we stopped sleeping in the same room." The Canadian actor claimed their sleeping arrangements shifted when Spelling allegedly brought animals — including a pig and multiple dogs — into their bedroom. The actor also said a chicken was living in their bathroom.

For her part, Spelling said on an episode of her new podcast, misSPELLING, that their divorce was "15 years" in the making.

"We always say, 'Hey, it made it 18 years. It shouldn't have made it 18 years.' And I think he would say the same thing if he and I had a real heart-to-heart. It would have been over a lot sooner," Spelling admitted, noting that they had a "very quick, passionate falling in love period" but there were "red flags" early on.

"I like saying that I just like to make dresses out of red flags and then proceed," she added.

Starting their family — which happened pretty soon after they met and married — also changed the pair's relationship, as Spelling noted, "Honestly, our relationship was never the same after we started having kids."