Meeting needs, from a question below

I was reading “How do I genuinely accept my husband as he is?” Below and the Answer the coach gave sounded beautiful. But, then I got confused at how that actually works in real life.

I know that the coach said she should meet her own needs. So what, then our partner can just do whatever ? And we just accept whatever? Or we state our requests and they can choose to do it or not. Then when they don’t, we can hold our power by leaving or by staying and finding ways to be happy and they can still just do whatever?

How is it holding your power for someone to walk all over you and you keep showing up for them?

I’m confused?