Lily Allen is feeling ''lost''.

The 'Not Fair' singer - who has daughters Ethel, three, and Marnie, two, with husband Sam Cooper - has sparked concern with her recent partying, which reportedly saw her collapse at Glastonbury and refused entry to the VIP area at Wireless festival, and insiders say she is going ''wild'' because she is struggling with her identity.

A source said: ''Lily is a bit lost and trying to find her place.

''She is so extreme and she's used to focusing on being one thing at a time; how to be a pop star, a mum and a wife - she's still working it out.

''It seems her default mode is to go wild because it's what she's always done.''

And Lily's husband is said to be upset by her recent antics.

A source told Britain's Grazia magazine: ''It's really hard for Sam. Lily has reverted to the person she said she never wanted to be again.

''But this is her career and the music industry has changed. Lily needs to evolve, and it's just a bit of a mess as she works out how.''