Demi Moore and Ashton Kutcher split almost a year ago, but time doesn't make it any easier for Moore to see her ex moving on with "Sexiest Woman Alive" Mila Kunis.

Moore is reportedly "not psyched" about Kutcher's new romance. "They're really serious," an insider tells Us Weekly of the former co-stars. "She's not psyched about Ashton and Mila."

"She was always insecure over the course of her marriage," the source adds. "So yeah, it's hurtful that he's with someone he knew the whole time he was with her."

Kutcher has known Kunis since being cast as Michael Kelso opposite Kunis' Jackie Burkhart in "That 70s Show," which premiered in 1998. In fact, Kunis revealed that Kutcher was her first kiss and that she had "the biggest crush on him" at the time, according to People. He also reportedly "always had a thing" for her, too.

Their on-screen romance turned into a real-life one back in April when the two were first spotted together.

Kutcher and Moore announced their separation last November after the "Two and a Half Men" actor was caught cheating. A 22-year-old woman named Sarah Leal claimed she and Kutcher had unprotected sex on his and Moore's sixth wedding anniversary, TMZ previously reported.

Still, nearly a year has gone by and neither Kutcher nor Moore has filed for divorce. RadarOnilne reported that sources speculate their 2005 Kabbalah wedding "was just a symbolic ceremony and not a legal marriage." Moore hasn't revealed why she has not filed for divorce, even though she was the one who first publicly announced the split.

Since breaking up with Kutcher, the mother of three was hospitalized in January after doing whip-its and reportedly checked into rehab at the Cirque Lodge in Sundance, Utah, for addiction and an eating disorder shortly after.

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