I am sorry you have such an insecure uneducated manager. Unfortunatley kroger does not give then any Phsycological testing of people skills before  putting them in people positions. document everything she says with date and time . always have wittnesses if you can and everyone needs to step up and start calling Hr. If she tries to belittle any of you again, just remind her that it is onley a grocery store and she is just a number like everyone else.