Jon Hamm and Jennifer Westfeldt have announced their separation. Hamm and Westfeldt, who have been together for more than 18 years, confirmed their split in a joint statement to a U.S. media outlet on Monday (7th September).

Jon Hamm and Jennifer WestfeldtJon Hamm and Jennifer Westfeldt at the New York premiere of Into the Woods in New York, December 2014.

Read More: Jon Hamm On What Happened to Don Draper.

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

Rumours about their relationship have been circulating for the past few months, partly fuelled by Hamm’s rehab stint for alcoholism in March. Shortly after his release from rehab, Hamm’s representative issued a statement on his behalf, announcing Hamm had completed rehab and emphasising Westfeldt’s role in his recovery. The couple have also previously responded to the rumours and, even as recently as April, they denied their relationship was on the rocks. 

The couple’s romantic relationship may be over but their professional relationship is likely to continue as they own a production company together, Points West Pictures.

44-year-old Hamm is best known for his role as Don Draper in Mad Men for which he won eight Emmy Awards. Screenwriter Westfeldt (also 44) directed and wrote the 2011 film Friends with Kids in which Hamm also starred. 

This summer has seen a number of celebrity couples announcing their separation after years of marriage. Although the summer is drawing to a close, could this trend of shocking celebrity splits continue into autumn?

Read More: Summer 2015: A Recap Of The Season Of Celebrity Divorces & Separation Rumours.