Oksana Grigorieva and Mel Gibson
02/19/2014 at 07:00 PM EST
Oksana Grigorieva – best known for her bitter court battle with her ex-boyfriend Mel Gibson
– has filed for bankruptcy.
The Russian singer, who has a daughter
, Lucia, 4, with the Oscar winner, claims she is more than $400,000 in debt and only has $10 cash to her name, PEOPLE confirms.
The 43-year-old, who claimed Gibson physically assaulted
her when they split in 2010, agreed to joint custody of their daughter in a settlement
in 2011. Gibson also agreed to pay her $750,000 in installments over the next five years and allow her to live in a house he owns in L.A. until Lucia turns 18.
According to the court documents, Gibson pays Grigorieva $20,000 a month in child support for Lucia, while former James Bond actor Timothy Dalton pays her $2,500 a month for their son, Alexander.
Grigorieva claims most of her debts are from legal bills from her court battle with Gibson and that she owes five lawyers $250,000. In 2013, she sued her lawyers for giving her bad advice regarding her settlement with Gibson.
was first to report the news.