The Desperate Housewives hunk and Coyle--a member of British girl band Girls Aloud--have been maintaining a transatlantic love affair since they met eight months ago.
The pair frequently spoke of their desire to marry and were last month reported to be house hunting in Los Angeles.
But friends claim the strain of balancing their busy schedules with a long-distance relationship has taken its toll.
A source tells British newspaper The Sun, "They had a tearful phone conversation at the start of the week and called it a day. They have both been flying to spend a few days with each other between work commitments. But it has not been easy.
"Nadine's work diary is filled up to 2008 and Jesse's film career has really taken off. It wasn't what either of them wanted but they felt they had no other option."
Article Copyright World Entertainment News Network All Rights Reserved.