sadecoco welcome to irv2
Sorry to hear of your problems. Is the switch rated to handle the current that will be going thru it?
Some MFG'S add to many items to switchs such as ignition and light switchs that will cause problems. Do you have other lights that are controlled by this switch and fail when switch fails?
Enjoy the forums and do post often.
A good automotive shop may help you out or give the model #'s of switch and someone can compare theres to yours for correction.