My SIL is visiting us, and she pinpoints mistakes in everything in our home. Like, she would start cleaning the bathroom or the jars in the kitchen and things like these and says in a laughing way that never mind, I will clean them, they look very dirty. All this makes me feel bad. What should I do? She never leaves an opportunity to embarrass me.

you know, some people exist only to try and show themselves superior by showing others down. this type of mentality exists so much in Indian families, where the in-laws are always trying to show the bahu down. the best thing for you to do here is to ignore this. in fact, i would say that you take this opportunity to make the best of her work and relax yourself ;) when she says things like this, reply saying that yes, i know you do these things so well and i am so not a typical housewife like you, so i am really happy that you take care of my home so well and that's why i won't stop you from doing so. ;)

Take it with stride. You can't change others but you can adjust and adapt yourself. I'll take it in a way that she is really helping me. And in return I'll thank her wholeheartedly