Honestly? I think it's survival instinct bro. Imagine you are stranded, you are powerless, and your captor who are supposedly stronger than u is wounded by assailant that you know could've done worse things to you. I'd choose my captor, as I'd choose the enemies I've known better. His survival is my survival at the current situation. Also there are the suspension bridge effect lol

Got raped and locked up by him and you’re still worried abt his wellbeing