Postcards from Mexico: Noche de Despecho, or where heartbreak becomes a party

It’s 10:15 a.m. on a Friday in a cantina in Valladolid. I’ve spent the last 10 minutes trying to figure out what I’ve walked into, but my only real lead is a table of a dozen 50-somethings singing and dancing to Timbiriche’s “Con Todos Menos Conmigo” over 2-for-1 cantaritos. As one caterwauls, the others use their straws like wands, stirring around tequila, grapefruit juice and years of sufferin…