What should one do if said person got too inebriated at santacon? thank you for your help in advance.

Apologize: Not sure what SantaCon is, but... Apologize formally to all you may have bothered, decide to limit or refuse alcohol and stick to it. If that's harder than you expected - find support. AA groups are the most successful and there's a wide range - if one doesn't fit, another might. You sound like a nice guy. I hope you can prevent it becoming a mess - you'll be so glad to have beat it early. Best!