I think the OP is trying to reference the concept of radical acceptance. It's about accepting your current reality, no matter how painful it may be. It's not about condoning said reality, but merely accepting that it's your current truth. From accepting it, you can then figure out how to work with it. Any text worth its salt describing radical acceptance will make absolutely sure you are aware that it isn't about condoning someone's actions.

It's a fucking difficult concept, but it does help as a jumping off point in my experience.

I'm kind of reminded of daoism as well. Daoism emphasizes the importance of working within one's nature. There are many things in life we unfortunately cannot change. But we can work with this and find our own path in the process.