CATHERINE Zeta-Jones's marriage to Michael Douglas finally crumbled after his oral sex bombshell.
The Welsh actress, 43, split from Douglas, 68, after he claimed that his throat cancer was caused by the HPV virus, which he contracted from giving oral sex.
Douglas did not make it clear he was exposed to HPV BEFORE meeting his wife, who felt this was the last straw.
A source said: "It all went downhill from there."
Zeta-Jones's own battle against bipolar disorder coupled with her husband's throat cancer ordeal are believed to have placed their 13-year marriage under intolerable pressure.
Wall Street star Douglas who is currently on holiday alone in Europe has recovered from cancer, but Zeta-Jones has been treated in rehab at least twice for depression, most recently in May.
It was at the end of that month when Douglas returned from the Cannes Film Festival following his oral sex bombshell that they finally decided to separate.
A source said: "The stress has taken a toll on their relationship."
The couple are currently "taking some time apart to evaluate and work on their marriage", a spokesman revealed yesterday.
However, the pair who wed in 2000 and have two kids together have been leading separate lives for more than a year.
One local near their country mansion in Bedford, Connecticut, said: "We have not seen much of Michael here with Catherine for about 18 months.
"Most of his friends are in New York. He likes the city and she likes horses and playing golf. They're like chalk and cheese."
Zeta-Jones has previously admitted how she struggled to cope after her husband was diagnosed with cancer three years ago.
She said: "I haven't had to deal with anything like that before. I wasn't as strong as I thought I could have been."
The couple also had to contend with Douglas' oldest son Cameron, 34, being jailed for drug-dealing in 2010.
The pair were last pictured publicly in April at a New York film bash. Since then, Zeta-Jones has spent time alone at her stables in Bedford while Douglas flew their children Dylan, 13, and Carys, ten, to Quebec for a holiday.
The couple are still talking as they decide on their future with lawyers not yet involved.
Douglas' first wife Diandra who he wed in 1977 when she was 19 and he was 32 was awarded around £30million when they divorced in 2000.
Douglas has since stated his biggest regret was not ending the marriage sooner. A pal revealed: "The last divorce literally nearly killed him, it took so much out of him financially and emotionally.
"He doesn't want to do that again unless he really has to."
A family friend added last night: "They want the best for their kids, no matter what happens."
Hours before the split was announced, Douglas arrived alone for dinner on Tuesday night at a restaurant in Nice, France, before meeting friends inside.
Zeta-Jones previously dated telly presenter John Leslie and Simply Red singer Mick Hucknall.
Douglas once paid tribute to her for giving him a "second chance to have a family", adding: "The thing I've learned about getting older is you can't take love for granted."