As you know, herpes is caused by Herpes Simplex Virus type 2. There are chances of recurrences year after year, after getting infected. But it is really rare to get more than 2 outbreaks a year. In your case, frequent sex sessions with your girlfriend, who already has got herpes might be the reason. So, the first thing you have to do is to make a log of your own activities in your life. It should include every action you do. You can spot out some causes which are triggering an outbreak too earlier, from the list you prepare.

In some people, further sex with infected people are seen causing an outbreak. Some experts recommend people to use water based lubricants to suppress outbreaks caused like this. But you should be beware not to use nonoxynol-9, oil based lubricants which can trigger an outbreak. This oil can cause vaginal irritation in some people and can result in heat breaking of condoms. Make sure that you are wearing condoms while having sex. In females, menstruation and related issues can trigger an outbreak. The main cause of frequent outbreak is a weak immune system. Your body immune system may be weak so that it cant withstand an outbreak so sooner. Stress is a villain which triggers herpes infection and symptoms. Lack of sleep, change in exercise sessions etc. also can cause an outbreak. Hope my answer was helpful. Take care.