I am wrestling with no contact, too (to a certain extent--not my fiancee)--I am so sorry this is happening.
Contact with people with that sickness can cause a lot of guilt. You're up against a POWERFUL DISEASE. He is not well enough to puzzle out how to be with you. Doesn't mean he can't get better, but you are not responsible for it.
Edit--I'm sorry to reinforce what others are saying. I saw your post too late. What a tough situation...just sending you comfort however you proceed.