I have a problem with self-reporting. It is often, especially when delivered in personal defense, self-serving. OP serves himself by making a case for his being terribly in love with Reeva, her not as much into him, and their relationship being mutually loving.
Doing so counters the theory he would be so enraged at her as to harm her. His claim that he was more in love than she garners sympathy and once again, goes to his not wanting to intentionally harm a person he is so besotted with. AND, let us not forget, Oscar is not only a gun-grabber, but a blamer. He gets ticked off, overwhelmed and off goes the gun through thee sun-roof, at the dog. And then it's all someone else's fault and he didn't do it, or not willfully. The tenor of his testimony about his feelings for Reeva and their relationship inequity implies that she's to blame for his shooting her. He was just trying to protect her, so mistakenly killed her to do so. IF (and remember, Oscar is covering bases in advance) it's established to any probably degree he did mean to kill her or scare her or reflexively shot but without lethal intent it's he we should feel sorry for and she who had the upper hand in the relationship, loved this worthy person less...In the OJ case, the jury felt Nicole had beatings and her killing coming to her. In a variety of ways, the defense made this case. Thus, jury nullification.
But the interesting thing is how transparent Oscar's strategy is in casting himself as the martyred one in a star-crossed love affair. That he doesn't see how others might perceive his testimony goes to a streak of the sociopathic in his character. Before the uproar--I did say streak. And I do not man to indict all sociopaths, in any case, as homicidal. Most are good salespeople, politicians, money embezzlers... A hallmark of the character disorder is blatant lying with seemingly no care for the fall-out ("I'll think about that tomorrow") coupled with an inability to read other people's emotional responses. Though this can undermine their credibility, it can also, paradoxically, lead others to be so incredulous that they will say "why would he/she commit to a glaring falsehood, when the truth could be determined later, or say something so appalling? He/she must be telling the truth as he/she knows it. He/she, in the second case, must not MEAN what she/he said. It's a slip.
I have a problem with those who believe wholesale what Oscar reports. Many (not all) who end up with criminal charges are, if not "born liars," sociopathic ones who acquire the habit to avoid the consequences of their anti-social behaviors.
Nel is trying to show this about Oscar. And since it's a cunning, baffling, and powerful trait he does well to do so.