Bitter Moon - Anyone else notice this about Mimi's transformation?

Okay, so I've probably seen "Bitter Moon" like, a dozen times? It's just so messed up and fascinating, lol. I always catch new things. But this time, I was really focusing on Mimi's character arc. At first, she's this sweet, kinda naive, almost ethereal dancer, right? And then Oscar just slowly corrodes her, like acid. But what I'm wondering is, when exactly do you think she fully snaps? I mean, there's the obvious stuff, like when she starts torturing Oscar back (the bedpan scene...yikes!). But I think it might be earlier, during that whole weird circus performance he forces her into. The humiliation seems a little too easy for her after that. Like, it's like she expected it. And the way she starts playing the game, out-Oscar-ing Oscar... that's not the shy girl from the Parisian bus, you know? And one more thing–do you think Oscar ever really loved her? Or was she just a canvas for his own warped desires? I'm leaning towards the latter, but there's that one scene where he's crying while watching her dance. Was that genuine sadness for what he was destroying? Or just him being a manipulative jerk (most likely)? I'm curious what other people think. Help me unravel this bizarre film!