You have a disability and you need to take treatment. Your health under law is the priority over another person's 'uncomfortable feelings'. It would be like telling someone to wear a mask because they had an unsightly facial scar, or insisting someone with a limb missing wore a prosthetic because people felt 'uncomfortable' - except in your case its worse as you need insulin and testing in order to live and stay healthy.

I don't know about the law in the US, but can't imagine on this issue it would be all that different from the UK, where employers have to make reasonable adjustments to accomodate the person with the disability or health issue - the person with the disability doesn't make the accomodation to deal with the ignorance and prejudice of colleagues. Were I in your position, I'd feel really angry.

Lee