I have a friend that chose to be a single mother but judges me for choosing to have children with three parents. "I would do that if children weren't involved" is how she puts it.
People sure are out there, thinking things, some of which are wrong. Often they say things we wish they wouldn’t. Sometimes they even do things that are unwise! It can be maddening when someone else’s perspective seems illogical or hypocritical. But it’s not within our power to change, usually.
If this friend is being judgmental of you, you don’t have to be her friend anymore. Or you can say “you’ve made your thoughts on my family clear; I’m not interested in changing to accommodate you, so let’s agree to disagree and drop this subject permanently.” If she can’t handle that boundary, well, you have a lot of information about what kind of friend she is. It hurts when people close to us are judgmental, and I don’t mean to dismiss that pain - but the only thing you can control is how much exposure to her judgment you allow for yourself.
If she is threatening your family - saying she’ll call CPS, or make a report to the kids’ school, or something - speak with a family law attorney and take the steps you need to protect your family. Otherwise, it’s best to leave her to live her life, as ignorantly or judgmentally as she wants.