When Mr Chen flew over to visit her with his brother Peter, the holiday was scheduled for 17 days but they left after a week because of the struggles their sister had with Mr Liu, he said.
Crown prosecutor Brian Dickey told the jury by late 2012 Ms Chen was so fed up she called her brother to tell him she was leaving the defendant and she was going to write a will excluding him as a benefactor.
It is alleged that Liu arrived home shortly after the victim on November 5 but that they did not go on their usual walk together.
Liu told police that Ms Chen went alone because he had injured his thumb while moving a pot plant.
"She never went out for that walk that night," Mr Dickey said.
"It's likely, although we don't have to establish it, that she died at home by the actions of the defendant."
Ms Chen's body was found 16 months after her disappearance, in a stream in Totaravale.
Mr Dickey said Liu had been familiar with the spot where the bones were found.
Ms Chen's body was so decomposed that a pathologist was unable to identify the cause of death. Mr Dickey said the defendant's story changed several times, and all the police interviews - which he called "powerful evidence" - would be played to the jury.
Police bugged Liu's house and phone lines. Seven days after Ms Chen went missing, he allegedly spoke to her soul, asking her why she was so jealous and ungrateful. Mr Dickey said the most important question for the jury was: "How did he know she was dead?"
The trial, before Justice Sarah Katz and a jury of six women and six men, will last up to eight weeks. NZME