Nicole Scherzinger is apparently feeling "drained and unhappy".

The 36-year-old has been super busy with work recently, promoting her new album Big Fat Lie and announcing she will appear in London's West End musical Cats.

Alongside this she's nurturing her on/off relationship with Formula 1 star Lewis Hamilton, 29, amid rumours she's keen for him to make a commitment.

And all the strain is thought to be getting on top of her.

"Nicole puts so much pressure on herself to succeed that she ends up burning out," an insider confessed to British magazine Star.

"Her solo career isn't going as well as she hoped, so she's throwing herself into other projects. But she's not looking after herself. She's drained and unhappy."

Last month Nicole caused concern when she reportedly asked her driver to pull over in rush-hour traffic because she felt unwell. Stopping would have been dangerous, so they had to continue on their journey.

"Nicole felt ill and was disorientated. She screamed at her driver to pull over, but he couldn't so she just opened the door," the insider continued.

On top of all this, it's thought the singer is keen to settle down, with marriage and kids on her mind. But with her hectic schedule and Lewis' busy working life, it's not that easy.

"Lewis is based in Monaco, while Nicole spends most of her time between London and LA. The distance can cause problems," the source sighed.

LATEST NEWS