Demi Moore faced a heartbreaking realization when the 60-year-old visited her ex-husband Bruce Willis after vacationing in Italy over the summer. Sources tell Closer that the beloved Die Hard actor — who’s been battling frontotemporal dementia — no longer understands she’s the woman he was married to for 13 years and the mom to his daughters Rumer, 35, Scout, 32, and 29-year-old Tallulah. “Demi kept in touch with the kids and Bruce’s wife, Emma Heming,” says an insider. “But she had no idea he’d gone so far downhill.”

The progressive disease can cause severe cognitive impairment as well as personality changes and mood swings. In Demi’s absence, the 68-year-old’s memory of her “faded,” explains the insider. “Demi could tell he really didn’t recognize her.”

On the other hand, adds the source, the Moonlighting alum still knows his wife and children and “expresses joy” when Rumer arrives with her new baby, Lou. At other times, Bruce can be “aggressive,” according to reports, while he’s also physically slowing down.

All of which is devastating for those who love Bruce. “Dementia is hard,” Emma told the Today show on September 25. “It’s hard on the person diagnosed; it’s also hard on the family,” she said, adding, “When they say this is a family disease, it really is.” Asked if her husband is aware of his condition, Emma replied, “It’s hard to know.”