Jon Hamm and Jennifer Westfeldt have split after 18 years together. Credit: Ilya S. Savenok/Getty Images

After 18 years together, Jon Hamm and Jennifer Westfeldt have called it quits. The longtime partners had been dating since 1997 when they met at the party of a mutual friend. 

"With great sadness, we have decided to separate, after 18 years of love and shared history. We will continue to be supportive of each other in every way possible moving forward," Hamm and Westfeldt said in a statement shared with Us Weekly.

"They've been fighting for a while, but now they're done,” a source close to Westfeldt tells Us. “They decided to finally split. It's sad."

Back in April, the couple slammed reports that they’d split prior to Hamm’s recent stint in rehab for alcohol addiction. 

"The story that appeared in this week's edition of In Touch magazine is not true," the Mad Men actor's rep told Us at the time. "The only gentleman Jennifer visited regularly in Connecticut was Jon, while he was in rehab. They continue to ask for the public's understanding and sensitivity during this challenging time." 

The pair last attended a public event together in January 2015, when they went to the Broadway show On the Town in NYC and posed with the cast. 

Though they lived together for many years, Hamm, 44, and Westfeldt, 45, never married and chose not to have kids. 

“I have a tremendous amount of respect for my friends who do balance this particular career with raising a kid, 'cause it's a tricky environment to bring them into... So not for us just yet,” Hamm told the Hollywood Reporter in 2011. 

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