blinker lights blowing out

I have a 99 camaro for about a year now and the drivers side blinker kept blowing out. after about 3 replacement bulbs the socket was burned so I had it replaced. 3 months later ( this past weekend) both blinker lights blew out at the same time. I bought 2 bulbs and noticed BOTH sockets are burned again?!!??!! I am putting the correct bulbs in because I get themn from a local parts store who punches the info in his computer. any ideas why they keep blowing out. the bulbs last for about a month before they blow out. but everytime the bulb burns out, the socket gets worse.