You may be exceeding the maximum lamp wattage of the fixture, creating too much heat. There should be a label inside the fixture that recommends the appropriate maximum wattage for that particular fixture. If the label is not there, consider replacing the fixture. Many times vibration is the culprit in short bulb life. There are vibration resistant bulbs for ceiling fans, garage door openers, lighting fixtures in high foot traffic areas, such as a 1st-floor ceiling light, or a light fixture near a slamming door. A rough service bulb would do well in these locations. Sometimes there are more than 120 volts being brought into the light socket. You can purchase a 130 volt light bulb to take care of this problem.