I am an DIYer and replaced bathroom light fixtures 3 years ago. Was using halogen and incandescent bulbs, but decided to switch entire house to LED. I admit that I purchased these bulbs from the dollar store and that may be part of the problem. Four of the nine bulbs have burned out after a few months. However, I just bought a new batch of bulbs from Home Depot, but do not want to install them if there could be another issue. It is in a bathroom and there are 3 fixtures chained together with 3 bulbs apiece. I believe the wiring is all correct or the fixtures would not have worked for 3 years? Right? The only other thing to note is that the switch itself is one of those lit ones that you see at night. That was also causing a problem with the LED bulbs glowing at night because they were picking up the current from the switch. Did some internet searching to solve that one. I changed the last bulb in the series to a different type of LED and the glow disappeared.
Do you feel it is the bulbs, switch. Or, possibly the wiring?