Sure I've felt judged. But I've gradually learned that when those judgements get me upset, it's ALWAYS because there is some element of truth in them, however small.
So, on my best days, I've learned to do 5 things, leaving room for the fact that all days are not my best days:
1. I avoid sarcasm, no matter how tempting. Sarcasm seldom has a positive effect on the critic and may actually confirm (in her mind) what a terrible person I am. And I want my child and grandchild to have a civil world to live in. Sarcasm or other forms of rudeness do not make the world a more civil, peaceful or happy place for anyone.
2. If it's possible to talk to them, I THANK the person who comments. I say something sincere, like "I'm so glad there are people in the world who care about the welfare of children! Thank you for your observations. I'm always working to be a better mother." (All true, right? And how could a person possibly go on criticizing me after receiving such a positive response?)
3. I consider the criticism objectively. In what ways might it help me be a better parent/person/citizen of the planet? We all have room for improvement, right? And whatever part of the judgement is that other person's issues, I just shrug and let it go.
4. I work on whatever part of number 3 is within reach, or might already be on my priority list. By doing this to the best of my ability and with the clearest of intentions, I rest happily in the knowledge that I'm being the best person/parent/grandparent I can. Nobody can ask more of me than that.
5. It also helps to keep in mind that people criticize, attack, and judge in other people what they can't bear to acknowledge in themselves. If you track this carefully over time and in all kinds of situations, you'll notice that it's always true. And of course knowing this makes me more hesitant to criticize, attack or judge other people. When I do, I'm looking in a mirror.