Hi, I'm new here. My boyfriend, who is sixteen years old whereas I'm 14, has stage 3 lung cancer and has had it for 2 years. He was diagnosed a little bit before we started dating. First, I'd like to say I know you will all say I'm young, but if you could look past that and try to be understanding with me and just give legitimate advice that'd be nice. 

2 days ago he told me that he had lung cancer, a 12% chance of living, and three months to live. Luckily, in a way, he was told that a year ago by the doctors, but he could still pass away earlier. I just cant seem to understand why something like this would happen to him of all people, he is the best person I know. He's the kindest, smartest person I know and yet things like this happen to good people instead of terrible people who could deserve this. Through the two years we've been dating he was so understanding whenever I'd talk about my problems and he still never told me I feel like I was so selfish. Even when I told him that I was sorry for being so selfish; he was still selfless enough to tell me "Babe its not your fault, you didn't know we all have our own problems that we have to try to cope with.". He's such a great guy and I'm not prepared to lose him I feel like I still sound selfish saying that, but I really dont wanna lose him. Any advice on how to prepare myself and how to help cheer him up whenever he does feel down about it? 

P.S. He moved to North Carolina a little while ago so we're also trying to keep it going long distance.