EROD

WTF? One of the few times I drive my '09 through the rain and I get home and the passenger headlight has water all inside the lense. Water has since dried out and left slight water marks on the inside...and worse, water that got inside was dirty so now there is dirt marks on the floor of the headlight assembly that are awfully visible...Is this a common problem or did I just get a bad seal? Car only has 35k but unfortunately already past the 4 years of warranty so I cant take it to the dealer. Am I SOL and have to replace the headlight assembly?