She's a "militant natural", so I wouldn't pay her any mind if I were you.
I never understood those types of people. I was natural for 3+ years and I didn't care what anyone else did to their hair. Heck, I was still applying relaxers on my friends and never gave any unwanted advice. I only gave advice when it was asked and I never put a person down for their choices.
Keep doing what you're doing and don't let the words of another sway your decision.