Will Forte and January Jones have called it quits on their relationship -- find out what went wrong Credit: Alberto E. Rodriguez/Getty Images

It’s over! January Jones and Will Forte have ended their relationship after just five months of dating, a source confirms exclusively to Us Weekly. The pair called it quits last month.

As previously reported, Jones and Forte met on set of their post-apocalyptic series The Last Man on Earth. They began dating in April.

The exes both attended the 67th Primetime Emmy Awards in L.A. on Sunday, Sept. 20 (No awkward run-ins at the ceremony or any afterparties were reported.) Jones, 37, spent most of the night celebrating with her Mad Men cast. Forte, 45, was nominated in the Lead Actor in a Comedy Series category for his Fox comedy role, but lost out to Transparent's Jeffrey Tambor.

As for why the actress isn’t on board with Forte, it may be due to the fact that she’s not looking for commitment. Jones has told pals that "relationships are a pain in the ass,” the insider says.

Jones, who is mom to 4-year-old son Xander, previously dated director Noah Miller until they split in January 2013. Prior to Miller, she was linked to Jason Sudeikis, Ashton Kutcher, and Josh Groban. She has kept the identity of Xander's father private.

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