That is absolutely 100% complete madness! I cannot believe there are insurance companies out there who will deny someone with a pre-existing condition, diabetes none the less! I have been blessed that my insurance has covered me 100% along the way, as I was diagnosed on my 20th birthday 
Not a great experience, but it sounds like you need some serious help! I have Northeastern Blue Cross Blue Sheild, and they even covered my OmniPod, which very few insurance companies are participating with. The pump is absolutely amazing, don’t stop trying!!! Get those insurance companies to make some things happen! (The pump is fantastic, and I’ve experienced much better bg control, please let me know how everything turns out) I wish you the best, and hope everything goes well,
Thanks 