For me, whenever I hear that someone is really sick, I'm worried about that person and that person's relatives but I do have hope that the doctor will say that person can be cured immediately or there nothing severe at all.
Hmmm.. First of all, I HATE summer. it's hot, stinks, sweaty, too much sunshine, bugs(mosquito),etc. So, every winter, when I feel super cold enough to go nuts, I recall the moments of summer. And I think, during winter, you can always find a way to warm yourself. However, during the summer, once you get all sweaty and stuff, there is no way to go back to the "clean" me. unless I take shower for 17th time a day. So... During every winter, I think of the moments of summer trying to be optimistic.
When something bad happens to me, for example, if I get a bad grade on my exams or my quizzes, I always try to think positive and I say to myself that I would get a better grade next time and study harder. That makes me feel better every time