Here's the thing though, that mom you think is watching you and picking apart how you parent... she is a little too busy with life and her own kids to focus on how you are doing things. Although, I bet she somehow has time to contemplate the possibility that you are judging her from the sidelines as well.
A friend of mine recently made me consider that when we talk about someone else "thinking" something negative about us, chances are that whatever we think they are thinking isn't what they are thinking at all, but rather it is what we ourselves are self-conscious about in the situation.
Moral of the story, relax and be kind to yourself. Assume she doesn't have anything negative to say about you. And get out of your own head and don't say anything negative about you either! My guess is you're a great mom and you are doing the best you can and making choices that work for your family. They don't have to work for anyone else's family - just yours.