The messages show a growing discord between the pair in April 2008, less than two months before Arias killed Alexander in a bloody attack that she claims was self-defense.
"Do not call back," Alexander wrote in one message read aloud in court today. "I'm sick of you playing stupid and dealing with your childish issues. Bitter feelings are brewing in me for you, and if it keeps up I fear I will have a genuine dislike for you before I have a revenge."
"You don't care about anything that doesn't involve you, and I'm sick of it, and I don't want to deal with any of it," he said. "It's wearing me out and if it continues, just like I have to give you motivation to tell me the truth I'll give you motivation to quit screwing with me," he said.
Arias is charged with murder for Alexander's death, and could face the death penalty if convicted. In her six days on the stand so far during her trial, Arias has described increasingly aggressive behavior from Alexander, who would show his "wrath" by kicking her in the ribs, cursing at her, and calling her names when they argued. One attack broke one of her fingers, Arias said, showing the court a permanently bent finger.
In one text message conversation, Alexander threatens Arias with "punishment." She explained on the stand that Alexander became obsessive about the identity of a stranger who told Arias that Alexander was cheating. A woman dining at the restaurant where Arias worked allegedly stopped her, identified herself as Marie, and told Arias about Alexander and another woman. Arias said she never learned the woman's identity.
"After tomorrow it's going to be really bad for you. It's time to spit it out," read one text message from Alexander about the woman's identity.
"I promise you the punishment will be better than the lie," read another.
The threatening texts and aggressive behavior drove Arias to move away from where Alexander lived in Mesa, Ariz., back to her hometown of Yreka, Calif., she said.
"I told him we need to spend more time apart, but not to get him out of my life. I wanted us to be able to have a friendship," she said.
But Alexander continued to have explosive reactions in their relationship, especially when he found out she was spending time with another man or sending messages to a romantic interest online.
"At this point it was just pure wrath," she said.
Arias, 32, is expected to testify this afternoon about the events leading up to the day in June 2008 in which she drove to Alexander's house, had sex with him, and then killed him.
The testimony comes as the trial enters its eighth week in Phoenix. The prosecution has laid out its argument accusing Arias of killing Alexander, her former lover, in a jealous rage that left him with 27 stab wounds, a slashed throat, and two bullets in his head. They say the murder was premeditated and that Arias lied about her behavior until she was cornered by evidence, and then changed her story to killing him in self-defense.
Arias' attorneys are attempting to convince the jury that Alexander was a controlling, abusive "sexual deviant" who used Arias as his "sex slave."