I'm sorry your friend feels this way. All of God's creations are precious. I am sure that your friend is going thru some major hormonal (sp) changes at the moment but for those of us who do not have skin kids our precious pets are our children (as well as those with skin kids, I know).
Your friend needs to get over it. Talk it out with her and tell her that your feelings are hurt by her actions and feelings. She needs to understand how much Cody means to you and accept that.