I'll bet you're right, and that she used to have curly hair. She probably didn't know it, and I'll bet *her* mother kept complaining about her hair and telling her to brush it (which, as we know, only makes it frizzy). She only knows how to deal with your hair the way her mother (or other caretaker) did it.
You know your mom best, and if this isn't possible, then ignore this advice, but here's what I suggest.
One day, when the two of you haven't been having a tussel over your hair, and when you're feeling loving towards her, ask her about what her hair was like when she was young. What did she love about it, what did she hate about it? What did other people in her life say about her hair?
You may find it easier to forgive her, after you hear her story. Depending on how it goes, you may be able to tell her that you're experimenting with ways to make your hair better. That things you've tried in the past haven't worked, and so you want to try this. Will she support you and break the cycle of hair hate that (I'm betting) has gone on, or can she at least agree to not say anything about it while you're trying to work things out. It's not like you're taking drugs or anything
No matter if you are able to have the conversation or not, I hope you understand that her hair issues are just that...hers. It has nothing to do with your hair, or how it looks, or how healthy it is. I don't know if her mother hated her curly hair, or if she was taught something along the line of "only tramps have curly hair" or what, but it's definitely her issues. Don't make them your own
Very fine, normal porous (Finally! Yay!), normal elasticity, loves high dew points.
Nature's Gate Tea Tree shampoo, GVP CB, Cure Care conditioner, aloe vera gel, Jessicurls products, Spiral Solutions products.
John Masters Organics Sea Mist
BioSilk Rock Hard Gelee (aka BRHG. It even has HG in the name!)
Last perm: 12/10/10
CG since: 3/9/12
Last haircut: 4/17/12