"This is one of those topics that makes me wonder: 'Why is anyone even talking about this?' Seriously, the only answer to someone who insists you must have children (and more than that, physically give birth, despite your raising children anyway), is 'Fuck you' and then not associating with that person anymore. Such people really are really just a waste of time and breath. That may seem harsh, but if you're such a waste of life, why should they talk to you anyway? More to the point, why the fuck should you talk to anyone who would degrade you that way?"
"I have no kids, I have no plans to have kids, and honestly, I think there should be more ways to prevent people who shouldn't be having children from having them, not the other way around. The world doesn't need more bratty children, broken homes, orphans, child abuse, and overpopulation. If you (and only you) felt an obligation to take care of more children of your own, there are plenty of children already out there that could use it."
"Either way, don't agonize over idiots that don't deserve your time. These are people who have deemed you less than them, people who think that they can make judgments over decisions you make that have zero effect on them. That's unacceptable behavior, and you should make that clear."