Separate Lives! Tori Spelling Suddenly Feels Like ‘A Single Mother’—Inside Why Dean McDermott Left

Even though it meant spending months away filming in Ontario, Canada, Dean felt they had no other choice as mountains of bills—including the $12,000 in child support he owes ex-wife Mary Jo Eustace for their 17-year-old son, Jack—piled up, long overdue.

However, insiders say it's a family decision Tori has come to regret.

Down to "only" one full-time nanny, the reality star, 42, has run herself ragged taking care of the couple's four children, Liam, 8, Stella, 7, Hattie, 4, and Finn, 3.

"Dean, on the other hand, apparently has plenty of free time," a source tells Star. "He spends his weekends out trout fishing and riding motorcycles with his buddies, but he's a no-show at both Hattie's and Finn's birthday parties? It's like Tori has become a single mother."

And to make matters worse, Tori spends most nights worrying that her husband, 48, will cheat again. (Back in 2013, Dean enjoyed a one-night stand with a woman named Emily Goodhand while in Canada to host the cooking show Chopped.)

"After everything that they've been through, Tori thought Dean would have been on his best behavior, but nothing's changed," says the insider.

"Dean's doing his own thing, checking with her less and less. He's putting her through hell," adds the tipster.