I have rheumatoid arthritis and I can understand your husbands want to bury his head in the sand and pretend he is okay, because it can be overwhelming to acknowledge the illness and to feel like others view you as sick. Ive had several acquaintances whove done the same thing as your SO, and as with most of these autoimmune illnesses, the longer you ignore it the more damage its going to do to you.

Personally I am deathly afraid of making my loved ones become caretakers. And its time he realized what a crappy position he is putting you in with his carelessness, because he might be too wrapped up in himself and ignoring his illness to think about it. Stop worrying about not pressuring him, dont excuse your concerns, and make sure he knows he needs to take care of himself if you are going to have a future together.