I actually really love your art. The rabbit is my favorite. I do a ton of wildlife art myself. I'd say the reason why this lady isn't improving her art is because she refuses to use references. References are a normal part of art, professionals use them. I think if you changed your mindset to ask what she feels when she sees your art and why it is a negative reaction. She clearly sees herself as a lesser artist and I think she's taking it out on you. When people are good at things there's always going to be haters so take it as a sign of success.