Left more than 100K profits on the table because of a work meeting

This happend on the 24th of June, I'm still bummed about it, random client meeting put on my calender for 9:30 EST, was holding covered calls on a stock that went up massively in the first 15 minutes. Had to cover the calls at a loss + sell 25% of my shares to cover margin, I'm still up about 200K but left 100K profits because of this stupid new client who isn't even replying to me now about the services

How do you get over this? I'm so pissed off