First time mom with HG, help???

I am currently 8W and have had intense nausea and vomiting since I was 4W, I ended up in the hospital and they told me I have HG. My OB has refused to take this seriously and has told me to try taking B6 over the counter, but that my insurance denied my anti nausea and vomiting medicine, I called my insurance to find out why, and they confirmed that my doctor's office has not contacted them and it definitely has not been denied. So now I feel betrayed my by doctor and scared for mine and my child's health, I can't end up in the hospital every other day because of dehydration from severe vomiting. Do any moms who have suffered from HG have any suggestions? I have already decided to find a different doctor, I can't go to a doctor who is willing to lie to me.