I would offer you some advice, but I am never good at it.
Don't give up, and hopefully you feel better writing it all down.
As for the cancer, I know this will sound lame but don't worry, I have had cancer twice, and at your age as well.
If you are worried and need to talk about it, please PM me, I understand what you are going through.

All I can offer you right is a great big ~HUG~