Im sorry to hear you are sick.
One thing you learn is that people that love you often tell you to be honest with them "just tell me if something bothers you", its a lie, because If you tell them the truth they will feel bad, nobody wants to feel bad, so when they say that, they hope you say "Im ok, thank you". This doesnt mean they dont love you, everyone is selfish in their own way, EVERYONE. Answering your question, I think most of us relate with you, they dont understand, you know what they want to hear and many times you are going to answer those things even if they are not true just so you dont feel like a burden to them... Its sad, but I still havent found anything that made me change my mind on this: we are alone, A L O N E.
"Just call me when you have an urge to hurt yourself" then you call and its "I have problems too, you are so selfish, have you stopped to think about how am I doing?" Ive lost count of how many times I fell for this... and you have to constantly remember yourself "they love you" because there is this voice telling you "nobody loves you"...
Again, Im sorry you have to go through this, I wish you find peace within your decisions.