Leona Lewis and Lou Al-Chamaa reportedly had a 'trial separation' before ending their relationship for good.

The 'Bleeding Love' hitmaker split from her long-term boyfriend last month, but pals admits the couple had been on the rocks for some time.

A source said: "This has been coming for over a year now, but Leona fought tooth and nail to keep things together. She and Lou actually went through a trial separation to see if that helped, but all it did was prove they are living separate lives. It will have been absolutely devastating for her to accept it was over."

One possibility the couple explored to save their ailing relationship was for Lou to quit his job in London to be with the singer in America.

The source explained to Look magazine: "Leona and Lou really wanted to make things work. They talked about him moving out to California but his life is in London and he's a home-loving guy. Leona is a global figure which means being in America for a lot of the time, and he wasn't interested in that type of life."

Leona's friend and mentor Simon Cowell is said to be worried about the star following her love split.

The insider said: "Simon realised very quickly that Leona was a sensitive girl who needed a reassuring arm around her shoulders. No wonder her team are getting worried about who will turn up in Lou's place. They were all big fans of Lou, because he was a stabilizing person in her hectic life."