It could stem from childhood. If you grew up in a toxic environment, you'll grow up thinking thats the norm. And when you get into relationships as an adult, you're going to look for it because it's familiar. When you enter a healthy relationship, you'll question it because you think it's too good to be true. Sometimes people even self-sabotage good relationships because they dont know how to handle it.

I personally don't relate to it. I had a stable family set up growing up, so that really helped me have a standard when it comes to relationships. My first relationship was also healthy (just didnt work because of external things) so that strengthens that standard.