Really really can't stand my MIL. She always disagrees with me and makes me look stupid in front of my own kids and husband. How do you stand yours?

I do not think you should accept the behaviour of your MIL, especially if she makes you look stupid in front of your kids. You can talk straightaway to your mother and tell her that she has no right to behave badly with you. And even you can do the same but it is your good values that bind you. If she doesn't mend her ways, then let your husband talk to her and make her understand the right way to behave. Thankfully, my mother never pins me down infant of my kids. Though, we have differences and do not gel but there never comes this kind of behaviour from her.