Rejoice when other scientists do not believe what you know to be true. It will give you extra time to work on it in peace. When they start claiming that they have discovered it before you, look for a new project.
We fear that this moment will end, that we won't get what we need, that we will lose what we love, or that we will not be safe. Often, our biggest fear is the knowledge that one day our bodies will cease functioning. So even when we are surrounded by all the conditions for happiness, our joy is not complete.