Christina Aguilera is reportedly really worried about tying the knot with her beau.

The singer has been dating Matt Rutler since September 2010.

Christina's divorce from ex-husband Jordan Bratman was finalised in April 2011, after officially separating around the same time she began dating Matt.

Christina lost a lot of money in her divorce from Jordan and does not want her reportedly $100 million fortune to decrease if she marries Matt.

"Matt has proposed to Christina at least three times he's desperate to marry her," a source told the National Enquirer.

"Christina swears she loves him, but the financial imbalance in their relationship is a huge concern. Matt was a low-paid production assistant when he hooked up with Christina.

"He doesn't have two pennies to rub together other than the allowance Christina gives him. His only paying job this year is helping to write some songs for Christina's upcoming album."

Matt's empty-handed proposals are of deep concern to Christina.

She feels that there is little substance behind the engagement.

"Christina's also bothered because each time Matt's proposed, he's done it without an engagement ring," the source explained.

"She knows that if they marry, she'll have to pay for everything."