Very disappointing, indeed! Don’t beat yourself up, though – just learn from the experience and move on. If the birds don’t come back soon, you may want to clean out the nestbox. They may come back for a subsequent nesting. In the meantime, you should baffle that post just in case it wasn’t a HOSP, but another kind of predator. If there was visible damage on the box, a HOSP wouldn’t have caused that. In any case, getting rid of the HOSP was a good thing! 
Central NY
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