Living with Huntington's Disease

My fiances father was dx with alzheimers. Of his siblings 3/5 have been dx. I am not sure about the 3rd, but I know one aunt has passed away at age 49. She was talking one month, got to the point where she didn’t know anyone, then passed all within about 3 months. His father’s disease progressed quickly also. He is 52 and is slouched in a w/c and can’t really speak, nor recognize anyone.

As i work in a hospital I have talked to Drs around here and they all feel that this is to fast and young for alzheimers and many have suggested huntingtons disease. My fiance is sure he will inherit his fathers disease and I would like to know how to help him! He is scared and doesn’t want to get tested (for huntingtons, alzheimers, anything). Not to mention he can’t tell me for sure if his father has been tested for other diesease such as this and not being married I can’t get the information without him.

How can I be there to help and get him to take action? I am really scared because I love him with all my heart and don’t want to lose him before we have a chance to grow old together.