Ben Foster and Laura Prepon just put a big X on their marriage: The “X-Men: The Last Stand” actor and the “Orange Is the New Black” star are divorcing after a yearlong separation. Foster filed for the split last month in Tennessee, where the couple ...

Ben Foster and Laura Prepon joined the growing list of estranged celebrities this year, but they shockingly separated a year earlier.

Foster cited irreconcilable differences as the reason for the split and listed their date of separation as Sept. 9 — the same day he filed for divorce.