AMY WINEHOUSE has penned a new song about her estranged husband's betrayal.
The singer wrote the track, believed to be called The Ultimate Betrayal, in light of newspaper reports at the weekend that Blake Fielder-Civil got 31-year-old Gilleen Morris pregnant when the pair met at a rehab clinic in Sheffield.
A source said: "Amy still felt they had something between them and that one day they'd be together again. But this news destroyed her.
"She sat down with her guitar and started writing 'The Ultimate Betrayal'. She keeps repeating the line: 'Blake a baby, no, no, no.' It's very haunting."
The source added: "Amy's best material was written when heartbroken by Blake, when he was two-timing her.
"But with all her problems we would rather she was happy than writing brilliant, emotive songs."
Winehouse is currently in the Caribbean island of St Lucia writing and recording tracks for her third album.