Casey Rodgers / Invision/AP 1 / 8
Casey Rodgers / Invision/AP 1 / 8

The revealing red Versace dress January Jones wore to Sunday's Golden Globe Awards may have seemed incongruous to the classic glamour she exudes on her hit show. But then, there's nothing like a fresh breakup to make you rethink your style, and Jones' relationship with "Saturday Night Live" funnyman Jason Sudeikis has ended, according to People.

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The 33-year-old actress was first spotted engaged in some serious PDA with Sudeikis back in July. Since then, they've kept a relatively low profile, perhaps in part for the same reason that they decided to go their separate ways.

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"They've been on and off for a few months and then the long distance kind of ended it," a source tells People. Jones plays Betty Draper in the Golden Globe-nominated AMC drama, "Mad Men," which films in Los Angeles, while Sudeikis' work on "SNL" keeps him stuck on the East Coast. "They could get back together," the source adds. "It was just hard to stay together with the distance."

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Other reports surmise that there may have been more than just distance riving a wedge between the lovebirds. "His friends don't understand why he's dating her," a source sniped to Us last summer. "They call her an airhead behind his back. She doesn't get their jokes. They've only known him to date smart, funny women."

In addition to her role on "Mad Men," Jones was recently named the face of Versace's 2011 spring/summer line.