mommamia, your MIL is likely a narcicist and cannot easily control her mouth. Most people have filters that prevent this type of behavior, but alas Hashem saw it fit for her to be born without this filter. What can you do? Well, you are not likely to change her. These are simply opportunities to work on your own middos. Try to set boundaries as respectfully as possible. Let her know when she has crossed the line, but again, be respectful. Bottom line, she cares for your kids and wants to do good by them, but she simply does not have the tools to do it in a way that does not offend. So make the adjustments on your end. And be sure your husband understands he may not take her side against you, even when YOU are the one who is wrong.