I think the OP you responded to is being intentionally obtuse, you have made your point clear repeatedly. If you are aware you have CF gene and are also aware your partner does too, then you will not mate with them and instead find another mate. Some diseases can be eliminated like this.
I also have a condition similar to you and there is no way I'm letting another child suffer with that, so I'm not going to ever mate with a woman who carries that gene.
I think the value in knowing upfront is you just avoid getting attached to begin with and you go bond with someone who doesn't introduce such big scary questions to the relationship. It is much easier to walk away before you get attached, no hard feelings. It is only when you fall in love first, have already invested substantial time into the relationship and then find out you both carry genes for something horrifying that it winds up being an agonizing question.
I also have a condition similar to you and there is no way I'm letting another child suffer with that, so I'm not going to ever mate with a woman who carries that gene.