Gillian Anderson splits with longtime boyfriend

Actress Gillian Anderson (L) and Mark Griffiths attend the UK premiere of Johnny English Reborn at Empire Leicester Square, London, on October 2, 2011. AFP PHOTO / FACUNDO ARRIZABALAGA (Photo credit should read FACUNDO ARRIZABALAGA/AFP/Getty Images)
Gillian Anderson and Mark Griffiths attend the premiere of "Johnny English Reborn" in London, on Oct. 2, 2011.

(CBS News) Gillian Anderson and her longtime beau, Mark Griffiths, have called it quits.

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A rep told Us Weekly the couple, who dated for six years, "amicably separated." Anderson and Griffiths have two sons together: Oscar, 5, and Felix, 3.

The 43-year-old "X-Files" star was previously married to film art director Clyde Kotz, as well as documentary filmmaker Julian Ozanne. Gillian and Kotz have a 17-year-old daughter together.

Anderson recently portrayed Miss Havisham in a new adaptation of Charles Dickens' "Great Expectations," which aired on PBS.

She will next star in a new movie with Michael Caine called "Mr. Morgan's Last Love." Anderson is also attached to the upcoming films "I'll Follow You Down" and "The Curse of the Buxom Strumpet," which co-stars Ian McKellan.