thanks to living in Japan, I've learned about mexican culture for events, parties, meetup. While in Japan they used to organize with too much time ahead and never have reminders but they have good culture about following their schedules and mexicans are totally different, we, as mexicans always organize everything the same day even with some hours before start deciding place and time. And also, mexicans need to remind everyday about the parties and meetups because we don't have agenda/schedule to follow up. These cultural things have pros and cons; mexicans cancel attendance quite often even at the same day, that's because they have too many stuff to attend that day and they have to choose one; priorities would be different, sometimes could be couple, friend, work, one time only event, exclusive events they haven't yet decide to attend, etc.
conclusion: mexicans are extremely living the moment.
I know you do your best my friend, but we're mexicans and we're happy with our lives.