Discuss this oxymoron in the comments below.
I've always had a problem with this expression. One of the factors for hope is that an outcome (the outcome hoped for) is not certain or is unknown. Hope may be idealistic or naive to the point of folly, but if the person who hold the hope believes that their desired outcome is possible then the hope exists. Hope is simply a state of mind. If the hoper feels cheated when an outcome is unfavourable, then to me this would be a false expectation, not a case false hope.