Although the pair had suffered from infidelity rumors after Lutz reportedly was seen kissing another girl at a New Year's Eve party, the breaking point came when Lutz failed to get McCord a birthday present. "She broke up with him. He wasn't a good boyfriend," a source close to the couple said.
The pair had been dating since late last year.
The source added that despite the New Year's kiss, "she forgave him." But on her birthday, "He showed up at her house with flowers and took her to dinner, but that was it," the source said. "No gift."
When Lutz tried to make amends by taking McCord on a vacation in Santa Monica to "get away," she declined to go, saying that the effort was too late. Reportedly, she decided to end things with the actor about a week ago.
MTV News contacted reps for both actors, but neither had confirmed the report by press time.
McCord has been linked to the "Twilight" franchise for more than just dating Lutz. She was almost cast in "New Moon" but had to pass on a role. "There was scheduling conflicts and I really just needed a break," she told MTV News in May. "I worked two years, I came straight off 'Nip/Tuck' and on to '90210,' and it's wonderful to work, but I needed some R&R."
Lutz seemed to announce his single status in July, despite being seen with McCord, but the news was not widely reported. In an interview with New York's Daily News, he said, "I'm very busy. I'm a relationship guy, but I recently broke up with someone who I was really in love with. And if that didn't work, how could anything else right now?"