Need Advice!!!!!

So I am a 17 year old female who has CF, my mother has multiple sclerosis and dementia, My grandmother has COPD and my littlest cousin has CF also, my whole life I have been surrounded by sickness. It is because of my mother I have decided to become a Neurologist ( brain and nerve system doctor) I have done all I can to prep for this, I graduated a full year early and have held high grades, I have always been ahead of my class even when I am hospitalized. My doctors do not think I should become any kind of Doctor because of risk I am taking. But all my life this is what I have wanted, there are some other CF people that are some kind of doctors, I just need to know ya'll thoughts. I have never really been sick or even had surgeries, (knock on wood). and I have been fully aware of my disease since I was 5, I was diagnoses at age 1, I know all my medications, their doses, and why I take them, I know what does not work for certain bacteria and ect, Ive known this since I was 10. So basically I know a lot about my disease and what I need to do for precaution, I just need to know what ya'll think, if I should continue my dream or give up now.