Not making friends on tour?

How many players have publicly said stuff like this?

I know Sharapova did, now Zheng also said similar stuff in her Vogue interview in China a few days ago.

Zheng said “I have not changed the thought (of not making friends on tour), because if I wanna make true friends, I’d want the best for them, but they’d also want to win, its difficult to compete with friends, they’d not be happy if they lose, and I’ll not be happy either if I lose…”

I have not heard this kind of statement in a very long time.