Is Strep Throat Contagious?

I have a friend who had strep throat and after 10 days of antibiotic treatment, I was with them! This person got strep again after kissing and then says I am a carrier! I have kissed many other people during this period and no one else has contracted Strep! I say she never got rid of the original virus, but she says I am a carrier! I refuse to believe this!