Hello! It is true that herpes can be recurrent and can occur everytime on contact with an infected person!once infected the virus has an acute phase where it stays for at least 21 days and slowly the ulcers heal.Many a time the male partner can harbour the virus beneath the foreskin and the female partner can have ulcers on the mouth of uterus also called cervix.Chlamydia is another common sexually transmitted infection which needs proper antibiotic course.As of herpes the drugs only reduce severity of symptoms and the virus clears off only after 3 to 4weeks time.So it is very important to have a single sex partner and to follow safe sex practices and using condoms.