Do you have a scan tool? What cylinder is misfiring?
Diagnosis is key before spending money. There's plenty of parts to swap around. Only swap 1 part at a time! Find out what cylinder is misfiring. clear the codes. Swap plugs with the cylinder next to it. IF the problem follows the spark plug, then replace the plug. If the misfire stays on the same cylinder, then clear the codes again and swap the coils. IF the problem moves to the other cylinder, then replace the coil. if not, then coils are fine. clear the codes again, pull the fuel rail loose and swap injectors between the problem cylinder and another cylinder. clear codes and run it until it misfires. see if the problem follows the injector or not.
If you are burning up coils, then it many times it's a spark plug that can cause coils to burn out. If the plug has too much resistance, or the gap is too large (worn plugs) then it requires the coil to produce more kv to jump the plug gap, shortening the life of the coil.