The Something Borrowed star split with the 34-year-old actor just five months after the couple announced their engagement, a source told People.
Goodwin and Kern, who were due to marry later this year, are planning to "remain friends" after ending their relationship "within the past few weeks".
The pair began dating in 2008 after being set up by a mutual friend.
Goodwin recently admitted to being "obsessed and enthralled" by the royal wedding.
Watch the trailer for Something Borrowed below: