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After 18 years together, Jon Hamm and Jennifer Westfeldt have decided to go their separate ways, ET confirms.

"With great sadness, we have decided to separate, after 18 years of love and shared history," the couple tells ET in a joint statement. "We will continue to be supportive of each other in every way possible moving forward."

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The couple’s last public appearance together was in late July, following the premiere of Netflix’s "Wet Hot American Summer: First Day at Camp." The two appeared together in 2011's "Friends With Kids," which Jennifer wrote and directed. That film was produced by Points West Pictures, the production company that Jon and Jennifer started together in 2009.

In April, Jon shot down rumors that he and Jennifer had split up.

"The story that appeared in this week's edition of In Touch magazine is not true," the couple's rep said in a statement to People 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."

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In March, the 44-year-old actor completed his treatment program with Jennifer by his side.

"With the support of his longtime partner Jennifer Westfeldt, Jon Hamm recently completed treatment for his struggle with alcohol addiction. They have asked for privacy and sensitivity going forward," his rep said in a statement to ET then.

In May, Jon seemed healthy and poised to move on from his now iconic role as Don Draper on "Mad Men," which wrapped up its final season that month.

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"I'm very happy," Jon said when asked how he felt about the outcome for his celebrated character. "I'm also happy that I get to go do other things too. It's a very bittersweet kind of thing. A mixture of feelings."

Of the shows legacy, Jon says, "The hope is… that the impact will outlast its time on television."

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