Chris Pizzello / Invision/AP 1 / 11
Chris Pizzello / Invision/AP 1 / 11

After 18 years together, Jon Hamm and his girlfriend Jennifer Westfeldt have split, according to a report. says In Touch Weekly is reporting Jennifer ended the relationship just before Jon entered a treatment facility for alcoholism in February.

"She told [him] it was over before he checked into rehab," a source told the publication. "She was tired of waiting for a commitment from Jon."

RELATED: Jon is "doing well" post-rehab

Since the couple had been together so long without a marriage, many assumed that Jon and Jennifer were happy with their arrangement. But In Touch's source says otherwise.

"Jennifer wants a life that Jon can't give her. Jennifer was tired of it," the source said, adding that the split was amicable. "People are happy for her and hoping she never takes him back."

Jon, though, has other ideas and reportedly wanted to rekindle the relationship.

RELATED: Amy Poehler: Jon Hamm told me to 'get my s--- together'

The reported split comes as Jon's AMC series "Mad Men" is also coming to an end after seven seasons. In the series, Jon's character was a hard drinking advertising executive. The actor said several times in media interviews that in real life he didn't drink as much as his character, Don Draper. Fiction, though, seemed to be become reality when he required rehab earlier this year.

RELATED: "Mad Men" cast: How their lives have changed

After it was announced that Jon had completed rehab in March, his rep implied that all was kosher with Jon's relationship.

"With the support of his longtime partner Jennifer Westfeldt, Jon Hamm recently completed treatment for his struggle with alcohol addiction," a statement from the actor's camp said. "They have asked for privacy and sensitivity going forward."