They won't steal your idea
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Do you fear people copying your life choices, responsibilities, and risks? If you answered "no", then you can be sure they won't steal your ideas, either.
You have changed your life to make your idea happen, you took the risks, and wrapped your reality around it. Nobody is going to go through the same process just to steal your idea.
What will happen, though, is people will help you achieve your goals. Because they will sense the urgency, the mission, in your behavior. If you let them.