her talking about you washing your hair or any of that has very little to do with her trying to help you. It's 1. her judgmental attitude and highly critical nature which is clearly shown here and 2. it's her over bearing and controlling nature trying to mold others into the image she feels is best for others. It's far from helpful and everthing about her behavior is about rejection of others that are "less than perfect" In her skewed view of the world.
I'm sorry but my impulse is to tell you not to put yourself in such situations and only deal with her when it's necessary. Why put yourself under undue stress like this?