ually attracted to Cars?

This all started when I was about 14. I stopped talking to girls almost entirely and began to be infatuated with cars. At the age of 15 i began to dryhump and then make love to Cars. I am not 23 and I still do this and find women unattractive. I am attracted to both Male and Female vehicles, no motorcycles. Is This normal, more importantly, can I get any mechanically transmitted diseases?