Anti-gay parents. What can I do?

My parents are Catholic (I'm not) and they keep texting me every two days begging me to choose to be straight. They don't understand and aren't willing to listen to me when I tell them it's not a choice. It's getting to the point of really affecting my mental health and I want to just cut them out of my life.

Is there any Christian literature I could send them that essentially makes them accept what I am, even if they don't agree with it? I'm just tired of opening my messages and seeing them talk about me like I'm a subhuman. At one point I'm just going to tell them "either stop saying those things to me or don't ever contact me again" and I know that will hurt them a lot.