Updated 13:14 GMT
Looking slightly more composed than he did on the previous day of his murder trial, Oscar Pistorius told a court that he was "besotted" with Reeva Steenkamp.
At this barrister's instruction, the Paralympian spent an hour and a half in the witness box reading out loving messages that passed between him and the model.
"I was very keen on Reeva. If anything I was more keen than she was," he explained, giving the court an account of the relationship, with tears streaming down his face.
The athlete arrives to give evidence for a second day
The sports star has denied killing her deliberately after an argument, saying he mistook her for a burglar.
After the couple met at a car event at the end of last year, the athlete asked her to be his plus one at an awards ceremony.
They had an "amazing time" on their first date, staying up talking until 3am, he said. After that the duo saw each other nearly every day, and spent the next couple of months getting to know each other before the relationship "really got going" in January.
Reeva's mother contained her emotions as he spoke
Both had come out of "difficult relationships". The South African sprinter said: "I let her just take her space - it wasn't always easy, I was besotted with her...
"The relationship built up to a point in December, January that we really... started caring about each other. We started talking about future plans."
Those plans included discussing the plans for decorating the house in Johannesburg where they hoped to live in together.
He also gave details of presents that Reeva was supposed to have given him for Valentine's Day. These were four framed photos of the two of them together plus a card. Oscar ended up opening them after the shooting, on her birthday.
During this part of his testimony her mother June Steenkamp looked on without betraying emotion - as she had on Monday when he offered her a tearful apology from the witness stand.
On Tuesday, her daughter's friend Gina Myers seemed visibly upset as the messages were read out. Reeva was living with Gina and her parents at the time of the shooting.
Oscar's sister Aimee became upset as messages between him and Reeva were read
During his examination Oscar's barrister also asked him to comment on arguments between the pair.
"I just think it was a bad hour in our relationship," he said about one row.
Of another, Oscar said: "I was a bit upset, I felt neglected... I was being sensitive, insecure... I wasn't kind to her like I should have been."
The athlete also spoke in detail about the night Reeva was killed, saying that he was adjusting fans in their bedroom when he heard a noise coming from the toilet.
"I just froze, I heard this noise, I interpreted it as someone climbing into the bathoom. I thought they could be there at any moment."
Selfie sent by Reeva to Oscar which was shown in court
"That's the moment everything changed," he said."I thought that there was a burglar that was gaining entry to my home."
He said he wanted to protect his girlfriend and went to get his gun.
"I whispered to Reeva to get down and phone the police," he said. "I was looking down the passage scared that the person, people were going to come out at that point. I rushed as fast as I could. I couldn't see anything in the room."