Six months after buying this truck the left headlight lamp burned out, ever since I have to replace a lamp every six to eight months. I dont buy cheap ones and I know not to touch the bulb with my fingers. they just burn out

I have been pulled over 3 different times for mechanical problems by state troopers. One time was less than 2 months after i had replaced both headlights and had the passenger headlight go out again. I would say in last 2 years i've replaced them about 5 or 6 times each.Luckily for me that the troopers gave me time to fix the problem and no ticket just warning.