I am suffering from the worst contact bounce I've ever seen.

I'm using the INT line on a PCF8574 and thought it latched until the chip was read... false... it latches until it is read OR is returned to it's original state (which offers no help whatsoever in the case of contact bounce!)... and the INTCON2.6 settings to work on rising or falling edges doesn't help either, so simply added a .1uF cap on the INT line right at the CPU to ground, and it 100% debounced the interrupt.

Sometimes a 10-cent hardware solution is still the best.