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The context would be in a romantic pursuit or a job opportunity - you've applied for the job and are waiting to hear back from them - you're constantly checking your emails, you're calling the receptionist to ask why they haven't got back to you (way to spoil your chances), etc.
Is there a word or phrase to describe this state.
Example usage might be a friend saying:
I think you're [over focusing] on this opportunity here. Maybe it'll all work out well - but in the meantime you should divert your attention somewhere else.