Very few things are in reality as bad as they seem to be in our imaginations. You have someone you must confront? Some person with whom you must be honest and open up your heart? It is only human nature to fear the worst from such a meeting, but the reality is most people are more reasonable than you give them credit for.
When Seneca the Younger said that we suffer more in our imaginations than in reality, this is what he meant: we can think of far worse to do to ourselves than someone else can, precisely because we know those things we fear the most.
But there is another side to keep in mind: so what if you confront that person and the worst comes to pass, if you open your heart only to be rejected? How is this any worse than what you were already imagining? I submit that not only is it not worse, it is in fact a better situation in which to find yourself. You see, no state of being is better than knowing the truth, and knowing how you actually stand with someone is much better than imagining your situation.
This, then, is the secret of right thinking: to have an attitude that says it is better to know the truth, however unpleasant, than to live in a fantasy.