C peptide is not antibodies. It’s an indirect measure of insulin production. Please tell me she’s ignoring this not failing to realise this. Menopause might be the weight issue but doesn’t answer the bgl. She might be happy with your levels but you aren’t and it’s your body. Sadly unless you can get a referral to someone who will investigate further it might be that you need to go private for this test. Others here have and might be able to guide you where and approximate costs.