I agree with you that was over the top. But exactly what kind of "secrets" do you think are deserving of being kept? Would you condemn me if, for example, I was told, in confidence, the whereabouts of a serial killer and I revealed the whereabouts to the police? Do you think admonitions not to bring Magic Johnson to a basketball game are worthy of being kept secret? So that if my spouse tells me not to hang out with my drinking buddies, there is some moral reason I shouldn't tell anybody what she said?
I don't recall everything that was on the tape, but I don't remember Sterling ever saying or implying "Now I'm about to reveal something to you in confidence" or saying anything that implies that he's revealing sensitive information that is never to be repeated. He doesn't reveal that he's considering a sex change operation or that he used to masturbate when he was fifteen or any deep personal secrets. He simply tells her a bunch of things that she's done that bother him.
Whatever wrong she did was a
private wrong between her and Sterling. She's a crappy girlfriend with a big mouth. But am I offended by what she did? Nope. Don't think I'd consider her as good girlfriend material (don't think I need to worry though; I'm an old fart, but doubt that I have enough money to attract her

).