GG, your husband's insurance company may be able to help you with the answer. I don't have experience with disability and medicare, but when my late husband was on hemodialysis, after 18 months he was automatically shifted to medicare as a primary insurance, with his work insurance as secondary. It was a nightmare dealing with "coordination of benefits" because each entity expected the other to pay for things which sometimes left us either fighting for someone to pay it, or paying it ourselves. But the good part was that there was still coverage from the employer insurance even though he had to use medicare first. That let him access services and coverage that Medicare didn't provide. Have you been told that you will no longer be eligible for coverage from your husband's insurance? If not, maybe you will still be able to see your LLMD thorugh his insurance. It's worth checking.
I have Lyme; it doesn't have me.