I know in doing interventions to get people into treatment, it is vital to be objective in pointing out the issues and frame it in such a way that the person isn't being attacked:

I feel _____________ when you ___________ because _________.

This seems to be a similar situation. If you make sure he understands that you all love him and worry about him, and be specific about what happened during the episode you mention by being blunt and pointing out exactly what happened - the facts.

Just my two cents.
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Well-behaved women rarely make history. - Laurel Thatcher Ulrich
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