The pal told RadarOnline, "Demi is devastated that Ashton has moved on so quickly and is dating Mila. She is beyond heartbroken. Even though Ashton cheated on her all the time, it was with random girls, it wasn't a relationship like it is with Mila and that is what is killing Demi now."
Kutcher and Kunis, who starred together on the hit TV sitcom That 70's Show, have been friends for many years and although they've tried to keep their romance under the radar, photos have emerged of the two canoodling on a date.
"Seeing photos of him kissing another woman is too much for her to handle, it's like having her nose rubbed in it time and time again," the source continued. "She kind of knew it was definitely over between them but I think she was still holding out a little hope for a reconciliation — now he's actually dating someone else she knows that's not going to happen."
The worst part? Kunis is more than 20 years younger than Moore, an age gap that cuts to the core of Moore's insecurities.
"Each time Demi hears about Ashton and Mila it breaks her heart. She really loved him despite the flaws in their marriage and to see him dating someone new, who is so much younger than she is, is like a knife in her heart," the insider revealed.
Moore and Kutcher split in Novembner 2011 after six years of marriage when it was revealed in a most public way that the puckish actor had cheated on her multiple times with multiple women — all of whom were significantly younger than his wife.
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