Per your picture, your hair is fabulous! Your friend may be uncomfortable because you've left the straight hair "team" -- where she's naturally very successful -- to do something that would be hard or impossible for her to do. So it calls into question a goal/value of hers. I agree with other posters that you should just tell her that curly hair is natural for you, like straight hair is natural for her, and you love your look, for you, like she likes her own look for her. With regard to healthiness, just about any straightening process from chemicals to blow-drying is much more damaging to hair than working with the curl.
By the way -- what do you use on your hair?? I'm 3b too but my curls are a little tighter and much frizzier. Whatever you're doing, you're getting a fabulous, HEALTHY look!