This is really a question which is to be thought about. So, thanks for your question. According to the statistics of US government, they have conducted and are conducting studies in people who have got infected. There are about 399 open and completed projects with them. But the results regarding the infections are not yet disclosed. And about the progress of study, it is slow and in progress. Studies are slow because viruses are too tiny organisms and studying them is really difficult. Moreover they are hard to crack. Researchers are trying hard to crack their codes so that antiviral medicines specific to a certain type of virus can be made. Anyway, we will surely win the battle over virus one day or other.
In your case with your girlfriend, you can prevent an infection. Better abstain from having sex with her because it is a sure-shot way of getting infected. Also, while she has an outbreak, make sure not to kiss her anyway or let her kiss you too. Also having oral sex with active outbreak will invite an infection. Also, while having sex, make sure that you use condoms. However condoms are not helpful in preventing infection as virus can be spread through skin to skin contact itself. Hope my answer helps. Take care.