You do not lose your curves by losing fat, in fact it is opposite: more fat you have rounder body you will have. I would recommend exercises focusing on your gluteal muscles.

I know what you mean.  I'm a curvy girl too and I'm keeping my curves.  I use weights.  Love to squat.  I do cardio at night as it helps me sleep but not to the extent of breaking the body down and yoga.  I am lean.  I have muscle and I have curves