Brooks Perlin and Katie Couric Brooks Perlin and Katie Couric

Katie Couric and her boyfriend of five years, entrepreneur Brooks Perlin, have split, People reports.

The breakup was "inevitable," a source tells the magazine, because the two were at different stages in their careers.

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Couric, 54, and Perlin, 37, met at a 2006 fundraiser for cancer research, and she was initially worried about their 17-year age difference. Her husband, Jay Monahan, with whom she has two daughters, died of colon cancer in 1998.Couric, who left the CBS Evening News in June, is working on her new syndicated ABC daytime show, Katie, which will begin in September.