What can I do about this dilemma I have?

Almost 10 years ago, I met a girl when I was in college and all of a sudden she stopped coming to school and we then chatted online. She finally told me that the reason why she left school was because she is terminally ill. She was afraid to tell me because she knows how emotional I get. We talk online as much as we can and one day she told me that her last wish is to be married to me. She said she wants to go happy. The other thing too is that we live in different places. I live in Chicag and she lives in Kansas. She wants to spend time with me next April but she said that when she goes back home, she ants to take me with her. She said it would be easier for her because in Kansas she has a home and she is more familiar with that area than where I live. I was born with spina bifida so I have always lived at home with my family because they can take care of me if need be. I have never been away from home. All my siblings have all married and have their own families now. The only one left is my youngest brother, but, he never is around to help our parents with their business. He only has time to spend with his girlfriend. I torn between these two things. My parents being alone when I get married and losing my future wife at any time. The other part of it is she is Muslim and I am a Catholic so we cannot marry in a church. What can I do? Thanks for the help.