Can my girlfriend or i get a sexually transmitted disease if we never had sex?

Only herpes: In general, STDs can only be acquired from someone who acquired them sexually from someone else. The only exception is herpes: hsv-1 usually causes cold sores and can occur in people who've never had sex. But it can cause genital outbreaks, especially in someone who gets infected for the first time. So it's possible for a "virgin" with a cold sore to give genital herpes to someone else.