Demi Moore hints of marriage trouble on Twitter. First picture of Sara Leal.

Demi Moore posted some thoughts about how to deal with “anger” on her Twitter account just on the night before spending the wedding anniversary alone last weekend.

Now, Demi Moore, 48, is facing claims she has “separated” from her husband of six years, Ashton Kutcher amid fresh rumors of infidelity.

Ashton Kutcher, 33, who is 15 years her junior, allegedly had a liaison with another woman after an alcohol-fuelled evening on Friday, according to website Radar Online.

The information was given by “multiple friends of the 23-year-old woman”, identified by another website as Sara Leal.

Sara Leal has reportedly hired a top Hollywood lawyer and gone into hiding.

It is the second time in a year that Ashton Kutcher has been accused of cheating on Demi Moore.

The latest alleged encounter happened on the 12th floor of the Hard Rock Hotel in San Diego, California, in the early hours of Saturday – the same day of Demi Moore and Ashton Kutcher sixth wedding anniversary.

Ashton Kutcher and the woman had apparently been partying at a club in the city. One fellow clubgoer said: “Ashton didn’t look like someone who was celebrating a wedding anniversary.”

It was the website thedirty.com which identified the young woman as Sara Leal and claimed she wanted $250,000 for her version of events.

The website added that “Kutcher told Sara Leal that him [sic] and Demi Moore are separated and the public doesn’t know yet.”

Ashton Kutcher’s bodyguard was also said to have taken Sara Leal’s mobile phone before she entered the hotel room.

On that same night, the eve of their anniversary, Demi Moore was tweeting from the East Coast, where she is temporarily based.

Demi Moore shared a quote from Greek philosopher Epictetus on September 23, writing:

“When we are offended at any man’s fault, turn to yourself and study your own failings. Then you will forget your anger.”

Three days later, Demi Moore, who has lost weight in recent weeks, posted a picture of herself looking forlorn, with the caption:

“I see through you.”

In other messages this month, Demi Moore said she was “trying to find the light I lost.”

The claims emerged as Star magazine reported: “Ashton and Demi have separated and the marriage is over.”

A source close to Demi Moore and Ashton Kutcher reportedly added: “The relationship ended because of Ashton’s serial cheating. It’s a painful time for Demi.”

Ashton Kutcher was first accused of infidelity in September 2010, when Brittney Jones, 21, said she had sex with the actor at the Beverly Hills home he shares with Demi Moore while she was away.

Brittney Jones told Star: “He looked over our texts and said he wanted me to delete all the messages from him. He then told me he wanted me to delete the texts I had sent to him. He said they could hurt him.”

At the time, the couple, who are worth an estimated $150million, brushed off the allegations.

Ashton Kutcher, who recently took over Charlie Sheen’s role in TV series Two And A Half Men, wrote on Twitter:

“I think Star magazine calling me a <<cheater>> qualifies as defamation of character. I hope my lawyer agrees.”

“Star magazine – you don’t get to stand behind <<freedom of the press>> when you are writing fiction.”

Ashton Kutcher’s spokesman also denied the allegation while Demi Moore tweeted “Excellent point my love!”

Demi Moore, who was previously married to Bruce Willis, started dating Ashton Kutcher in 2003 and they married in 2005.

2011 is the first year they spent their anniversary apart. Demi Moore was in New York to promote a short film which she has directed called Five, while Ashton Kutcher headed to San Diego to party with fellow actor Danny Masterson.

Representatives of Demi Moore and Ashton Kutcher have not commented so far.