Amber Heard was by mother-in-law's side despite failing marriage - report

Amber Heard reportedly played the dutiful daughter-in-law by making regular visits to see husband Johnny Depp's ailing mother prior to her death.

The actress filed for divorce from her husband of 15 months on Monday (23May16), just three days after Johnny lost his beloved mom, Betty Sue Palmer, following a long illness.

Reports have since surfaced suggesting the couple's marriage crumbled because Johnny's family did not approve of Amber, but a source close to the actress insists that wasn't the case, and the 30-year-old blonde had actually formed a close bond with her 81-year-old mother-in-law as her health deteriorated over the past year.

"Amber was by Betty Sue's side during this illness," the insider told People.com, "and regularly visited her in the hospital."

The pal goes on to claim the actress is "a family person," adding, "Amber was the one that suggested that they get married at Betty Sue's house."

The estranged couple tied the knot in February, 2015 after first meeting on the set of 2011's The Rum Diary.

In her legal papers, Amber listed irreconcilable differences as the reason for their separation, which officially began on 22 May (16). She is seeking spousal support, but her bid for financial help has been challenged by Johnny, who is asking a Los Angeles judge to deny her request.

He has hired top celebrity divorce lawyer Laura Wasser to represent him in court.

The couple has no children together, but the 52-year-old actor has two kids from a previous relationship with his girlfriend of 14 years, Vanessa Paradis.

Neither Johnny nor Amber have commented on their marriage breakdown.