"I'm scared of u sometimes and how u snap at me and of how u will react to me," Reeva Steenkamp texted Pistorius, in a message read in court by police Capt. Francois Moller.
In another message Steenkamp wrote to Pistorius: "I can't be attacked by outsiders for dating u AND be attacked by you, the one person I deserve protection from."
Moller said that from Steenkamp's phone he obtained more than 1,000 exchanges with Pistorius on WhatsApp and other phone messaging applications. Moller said he received as evidence two BlackBerry phones, two iPhones, two iPads and a Mac computer from Pistorius's house the day after the shooting death of Steenkamp.
The data on Steenkamp's phone would print to more than 35,000 pages, said Moller. Of the fraction of exchanges between the couple, he said that about 90 percent were what he called normal and "loving" exchanges.
In Steenkamp's message about being scared of the athlete, she also added: "You make me happy 90 percent of the time and I think we are amazing together." She goes on to talk about Pistorius snapping at her about chewing gum and talking in an accent, and then writes: "I just want to love and be loved. Be happy and make someone SO happy. Maybe we can't do that for each other. Cos right now I know u aren't happy and I am certainly very unhappy and sad."
The long message was sent after the two attended a friend's engagement party and apparently left early because she said he got upset and jealous. As Moller read the message, Pistorius, who had been looking at a book of the compiled messages, closed his eyes. His face became red, and tears fell to his lap. He then wiped his eyes with a white handkerchief and regained the composure he held through most of the day.
The double-amputee apologized for his behavior in replies to Steenkamp's message, according to the testimony.
Moller also read messages exchanged after a shooting incident at a Tashas restaurant about a month before the fatal shooting. Boxer Kevin Lerena and Darren Fresco testified that Pistorius asked Fresco to take the blame for a shot that went off after the loaded gun was passed to Pistorius under the table.
In the phone message exchange, the 27-year-old runner explained to 29-year-old Steenkamp: "Angel, please don't say a thing to anyone ... the guys promised not to say a thing," he wrote. She then replied: "I have no idea what you're talking about "
Investigators tried to access information on Pistorius's locked iPhone for months and met Apple officials in the United States just before the trial started on March 3. Pistorius said he forgot the password to his phone.
Earlier Monday a neighbor testified that she heard gunshots as well as screams from both a man and a woman on the night that the double amputee runner fatally shot Steenkamp.
Anette Stipp's testimony matched some of the evidence given by other witnesses earlier in the trial who said they also heard a woman screaming around the time that Pistorius killed Steenkamp before dawn on Feb. 14, 2013. According to Pistorius's version of events, he thought Steenkamp was in bed when he fired his 9 mm pistol. He did not describe any woman screaming.
The defense has countered that the neighbors actually heard Pistorius screaming in a high-pitched voice after he shot Steenkamp. Pistorius has said he shot his girlfriend by mistake through a locked toilet door, thinking that she was an intruder in his home.