Debra Messing Files for Divorce From Daniel Zelman

There's nothing messy about Debra Messing's divorce proceedings.

The Smash star, 43, filed papers Tuesday asking a judge to end her nine-year marriage to actor and TV producer Daniel Zelman, E! News reports. The actress is seeking joint physical and legal custody of their 8-year-old son, Roman.

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Messing -- who met Zelman at New York University in the '90s and tied the knot in September 2000 -- listed their date of separation as February 15, 2010; the spouses continued to live together until early 2012. When Us Weekly broke the news of their split in December 2011, a rep for the New York-based couple explained that they would "gradually transition into a new living situation."

Though Messing has since moved on with her Smash costar Will Chase, 41, her impending divorce still weighs heavily on her.

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"Twenty years. It's a very long time," the Will & Grace alum recently told Ladies' Home Journal. "I think the institute of marriage is a noble thing. I think the idea of a partner for life is incredibly romantic. But now we're living to 100. A hundred years ago people were dying at age 37. Till death do us part was a much different deal."

Messing added that she's beginning "a new chapter in my personal life" and "walking a path I've never walked before." Fortunately, she and Zelman are still on good terms.

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"Every thought is dictated by what's best for our son. [Daniel and I] are completely on the same page in that regard. We are dear friends. And I am at peace with the journey we've had," she told Ladies' Home Journal. "I feel like the 20 years we had together has been a huge success. And despite the fact that everything is changing, I think everyone is thriving."