On topic the second (behavior of hope), there has been research on how uncertainty amplifies the emotional impact of an event by preventing people from coming to terms with the event and adapting to it. This is true for both positive and negative events. Wilson and Gilbert (2008) have a review article on their model of adaptation which incorporates this effect. The abstract:

We propose a model of affective adaptation, the processes whereby affective responses weaken after one or more exposures to emotional events. Drawing on previous research, our approach, represented by the acronym AREA, holds that people attend to self-relevant, unexplained events, react emotionally to these events, explain or reach an understanding of the events, and thereby adapt to the events (i.e., they attend less and have weaker emotional reactions to them). We report tests of new predictions about people’s reactions to pleasurable events and discuss the implications of the model for how people cope with negative events, experience emotion in different cultures, and other topics.

You can search their paper for the keyword "certain" to find the relevant portions. Gilbert, Wilson, and their colleagues also have several recent studies on the emotional impact of uncertainty, although they have tended to focus on relatively minor events and on positive emotions more than negative ones. Here are the references for their recent articles; you can find the papers on Google Scholar or Gilbert's website.

Wilson, T. D., Centerbar, D. B., Kermer, D. A., & Gilbert, D. T. (2005). The pleasures of uncertainty: Prolonging positive moods in ways people do not anticipate. Journal of Personality and Social Psychology, 88, 5-21.
Kurtz, J. L., Wilson, T. D., & Gilbert. D. T. (2007). Quantity versus uncertainty: When winning one prize is better than winning two. Journal of Experimental Social Psychology, 43, 979-985.
Wilson, T. D., & Gilbert, D. T. (2008). Explaining away: A model of affective adaptation. Perspectives on Psychological Science, 3, 370-386. pdf
Bar-Anan, Y., Wilson, T. D., & Gilbert, D. T. (2009). The feeling of uncertainty intensifies affective reactions. Emotion, 9, 123-127.
Whitchurch, E. R., Wilson, T. D., & Gilbert, D. T. (2011). He loves me, he loves me not: The effects of uncertainty on romantic attraction. Psychological Science, 22, 172-175.