Just speaking from my own experience. When I was involved with my ex, I was absolutely delusional about expectations. I told myself that if I never expected anything from him, I wouldn't be surprised if he let me down. It was a miserable way to live. And it didn't last very long either. What I learned is that it is ok for me to have boundaries/expectations when it comes to how others behave towards me. It's just not ok for me to expect them to change the way they behave because I don't like it. But I don't have to accept their behavior. I can walk away or tell them to leave.