Demi Moore and Ashton Kutcher frequently got into "intense" arguments with each other before they split, according to a source.

Demi officially announced that she and Ashton are getting a divorce after six years of marriage on Thursday. The couple's relationship is thought to have been strained for months due to allegations that Ashton cheated on Demi on their sixth wedding anniversary with 22-year-old Sara Leal in September.

A source close to the shattered couple believes that there other insurmountable problems existed in their relationship.

"The fighting could get pretty intense," a source told People magazine. "Whatever counselling they did was fine for a quick fix but could not get to the heart of the problem."

The conflict got so heated that the Demi and Ashton were compelled to call it quits.

"Ashton is unhappy; Demi's unhappy," another insider told the magazine. "It just got to a point where they had to end it."

Ashton has spoken recently about his approach to maintaining happy relationships.

"I think it's all about working on the relationship and making it betterwhen it's good," he explained to the December issues of Men and Women's Health magazines.

"Don't wait for a problem to work on things. The goal is not to get into a relationship; the goal is to be in a relationship."

The pair will allocate nearly $290 million worth of marital assets between themselves during divorce proceedings.

It is unknown when their marriage will be officially dissolved.