Someone, please explain to me how the fuck I'm supposed to "be confident" when I have shit like that said to my face.

No one really understands this when they don't have an issue with it. You can't really build confidence from nothing. It was really a pleasure one time where my female friend told me I just need to keep trying and when just casually mentioned how about she sets me up with one of her friends she says 'well they are too tall for you.' That really makes you feel more confident when even your 'friend' can't even feign hope to build off of.

It isn't worth the constant humiliation and reminder that I suck. I'm not mad at women for it. I get it. I can't make them want something they don't want. I'm just mad at my genetics for making me this way.

I 100% don't want kids for this reason. Even if I find a SO, there is a ~50% chance that it will be male and I don't want to hand down my shitty genetics to him.

I feel for you man, it truly does suck when you feel like you have to prepare yourself to spend the rest of your life alone.