I have had some issues that have convinced me that I will never try and have/raise kids.

This, however, leads to some serious problems when dating/having a relationship with people. I always make it a case to mention to people before starting to date them that I don't want children and that I don't want them to hope/expect me to change my mind. I just straight out tell them what I just wrote here.

Most of the time, this means we just part ways as good friends before the dating even starts. But in other cases, people say they're fine with both points.

So, I get happy, thinking I finally found someone I can happily share the rest of my life with. Often though, when dating people, the topic of kids is bound to come up again, (either by seeing a misbehaving kid, attending a birthday party where a well-meaning relative starts to tease)... So far, the record is 6 dates before the date will inevitably say something along the lines of

Well, you'll change your mind when you're older, I'm sure / I'm hoping she'll change her mind on that.

I often follow that up with a talk asking about how serious they were, they'll admit that they are serious and I end up breaking up (telling them I won't take the dating any further) then and there, disappointing both of us.

So, now I have both trust issues and the idea that I'm not communicating this right, that I'm missing something.

How can I stress that having children is really non-negotiable and that I don't want people to be misguided about that?