Hamm and Westfeldt, who had been together for 18 years, confirmed the break-up to People, saying in a joint statement that the decision was amicable.
"With great sadness, we have decided to separate, after 18 years of love and shared history," the statement said. "We will continue to be supportive of each other in every way possible moving forward."
The "Mad Men" star and the "Friends with Kids" actress had been an enduring symbol of stability in quickie marriage-obsessed Hollywood, and had been together since 1997. But rumors of a split surfaced earlier this year, around the time that Hamm revealed he had entered rehab for alcohol addiction, and though they denied any trouble at the time, the cracks were apparently already beginning to form.
Still, it's shocking to see a devoted duo abruptly end a relationship, especially one as PDA-friendly as Hamm and Westfeldt. Their bond was so deep that Hamm famously told Westfeldt how "Mad Men" ended, long before AMC aired the final episode. If that's not love, then we don't know what is.
Here's hoping both find happiness moving forward.
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