Lately my mom's been struggling with trying to stop using shampoo, dyes, and other products in her hair which she thinks have been responsible for damaging it a lot over the years. I think it is especially tough for her because right now her hair does not meet typical standards of beauty and when she was my age a very large portion of her sense of self-worth was tied up in her physical appearance.
I have found it useful to stroke her hair and head and smile at her when she is having a rough time with it. Even though she doesn't necessarily "like it" in the moment (the first time she said "ewww, oily" and took my hand and tried to wipe it on my pants), I think it helps.
Trying to get rid of so many years of societal programming related to hair and appearance must be tough. Being a dude it's not something I have experienced directly, but I can empathize.